Tertia Pars #

A study of St. Thomas Aquinas’s Tertia Pars (Third Part of the Summa Theologiae). These lectures examine the Incarnation, the life and work of Christ, His Passion and Resurrection, and the sacraments through which grace is communicated to the faithful.

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Lectures #

1. Jewish Knowledge of Christ and Voluntary Ignorance #

This lecture examines whether the Jewish persecutors of Christ knew Him to be the Son of God, exploring the distinction between knowing Christ as the promised Messiah versus knowing the mystery of His divinity. Berquist follows Thomas Aquinas’s resolution that the Jewish princes possessed knowledge of Christ from Scripture and miracles but willfully rejected this evidence through envy, constituting a voluntary or affected ignorance that does not excuse their sin. The discussion introduces figures of speech (antonomasia and synecdoche) as interpretive tools for understanding scriptural language about Christ’s divinity and humanity.

2. Structure of Sacred Doctrine and the Incarnation #

This lecture examines the organizational structures of Thomas Aquinas’s Summa Contra Gentiles and Summa Theologiae, comparing how each arranges the treatment of God (in Himself, as Maker, and as End). Berquist explains why the Incarnation is placed differently in each work—under ‘God as Maker’ in the SCG but under ‘God as End’ in the ST—and introduces the six central questions for understanding the Incarnation, particularly whether it was suitable and necessary for human redemption.

3. The Suitability and Necessity of the Incarnation #

This lecture addresses whether it was suitable and necessary for God to become incarnate, examining objections based on divine immutability, the infinite distance between God and creatures, and whether God could have redeemed humanity without incarnation. Berquist explores Thomas Aquinas’s responses through the lens of divine goodness, the two senses of necessity, and the theological advantages (faith, hope, charity, example, and deification) that the Incarnation provides for human salvation.

4. The Incarnation’s Suitability: Summa Theologiae and Summa Contra Gentiles Compared #

Berquist compares Thomas Aquinas’s treatment of why it was suitable for God to become man across two major works: the Summa Theologiae and Summa Contra Gentiles. The lecture examines the distinction between absolute necessity and necessity “from the end,” argues that the incarnation was most suitable rather than absolutely necessary for redemption, and systematically presents arguments showing how the incarnation removes impediments to human beatitude and awakens hope, faith, and charity in us.

5. The Suitability of the Incarnation: Arguments and Synthesis #

This lecture synthesizes and compares arguments for the suitability of God becoming man from both Thomas Aquinas’s Summa Theologiae and Summa Contra Gentiles, organizing approximately thirteen distinct arguments across faith, hope, charity, example, dignity, satisfaction for sin, and other theological considerations. Berquist also addresses the theological question of whether God would have become incarnate if man had not sinned, presenting Thomas’s position that Scripture consistently presents the Incarnation as a remedy for sin, while acknowledging God’s absolute power to act otherwise.

6. Suitability of the Incarnation and Its Timing #

This lecture examines Thomas Aquinas’s arguments for why God becoming incarnate was suitable and appropriate, drawing from the Summa Theologiae. Berquist explores thirteen reasons for the Incarnation’s suitability, addresses whether it would have occurred without sin, and explains why the timing—neither immediately after sin nor at the end of time—was providentially ordered. The discussion emphasizes the role of humility in recognizing sin, the pedagogical progression through natural law and written law, and the proper fervor of faith.

7. The Union of the Incarnate Word in Person, Not Nature #

Berquist examines Thomas Aquinas’s response to whether the union of the Incarnate Word occurred in nature or in person (Question 2, Article 1 of the Tertia Pars). Through a careful analysis of what ’nature’ means and three possible modes of union, he demonstrates why the two natures of Christ must remain distinct while united in a single divine person. The lecture establishes the crucial metaphysical distinction between nature (essence) and person (individual subsisting substance) that is foundational to Christology.

8. The Incarnation: Union in Person, Not Nature #

This lecture examines why the union of divine and human natures in Christ occurs in person rather than in nature. Berquist systematically refutes three possible modes of composition (perfect integral things, perfect changed things, and imperfect things) before establishing the fundamental distinction between nature and person, demonstrating that everything in a person is united in that person. The lecture draws heavily on Thomas Aquinas’s Christology and conciliar definitions to clarify this central mystery of Christian faith.

9. The Hypostatic Union and Unity of Person in Christ #

This lecture examines the precise theological and philosophical terminology surrounding the Incarnation, focusing on how the divine and human natures unite in the single person of Christ. Berquist addresses the distinction between hypostasis (suppositum) and person, clarifies why the union occurs in the person rather than the nature, and resolves apparent contradictions about whether Christ’s person is composite. The lecture emphasizes linguistic precision across Latin and Greek terminology to avoid ancient heresies, particularly Nestorianism and its variants.

10. The Hypostatic Union and the Soul-Body Composition in Christ #

This lecture examines whether Christ possessed a true union of soul and body, and addresses the metaphysical status of the Incarnational union itself. Berquist systematically refutes objections claiming that a soul-body union in Christ would create a new person or hypostasis, clarifying instead that in Christ the soul and body unite to subsist in the pre-existing divine person. The lecture explores the distinction between accidental and hypostatic union, drawing on Damascene, Thomas Aquinas, and conciliar definitions to defend the Catholic understanding of Christ as truly man and truly God.

11. The Union of Divine and Human Natures in Christ #

This lecture examines the hypostatic union—the union of divine and human natures in the one person of Christ—distinguishing it from heretical alternatives like Nestorianism and Eutychianism. Through careful analysis of key Church councils, Aristotelian metaphysics, and Thomistic theology, Berquist explores why the union is substantial (in the hypostasis) rather than accidental, how it relates to the nature of relations in metaphysics, and whether the union itself is created or uncreated. The lecture emphasizes the importance of precise terminology regarding nature, person, hypostasis, and subsistence for understanding this central mystery of faith.

12. Relations, Union, and Assumption in the Incarnation #

This lecture explores the metaphysical nature of relations through the lens of the Incarnation, focusing on Articles 7-9 of Aquinas’s treatment. Berquist examines how the union of divine and human natures constitutes a relation created in the human nature (but only a relation of reason in God), clarifies the distinction between union and assumption using Aristotelian principles, and argues that despite the infinite distance between the natures, this union represents the greatest of all possible unions when considered from the side of the divine person as the term of union.

13. Distinction of Reason and Real Distinction in Theology #

This lecture explores the subtle distinction between real distinctions and distinctions of reason, particularly as applied to understanding the Trinity and the Incarnation. Berquist uses examples from mathematics (numbers with different factorizations, square and cube numbers) to prepare students for comprehending how something can be affirmed of one thing and denied of another without implying a real distinction—only a distinction in thought. The lecture culminates in applying these principles to Thomistic theology, especially regarding grace and the union of natures in Christ.

14. The Grace of Union and Divine Assumption #

This lecture explores whether the Incarnation was merited and whether the grace of union is natural to Christ, then transitions to examining whether assumption belongs to divine person or nature. Berquist analyzes how the hypostatic union transcends habitual grace, clarifies the meaning of ’natural’ in Christology, and begins investigating the metaphysical structure of divine assumption.

15. Divine Nature, Assumption, and the Incarnation #

This lecture explores whether divine nature (as opposed to divine persons) can assume human nature, how the human intellect can abstract personality from God’s nature, and whether divine persons other than the Son could have become incarnate. Berquist works through Thomas Aquinas’s treatment of these questions, emphasizing the distinction between the act of assumption (proceeding from divine power common to all three persons) and the term of assumption (the divine person to which human nature is united), and clarifies how both God’s simplicity and the Trinity inform these theological conclusions.

16. Multiple Divine Persons and Natures in the Incarnation #

This lecture explores two hypothetical theological questions: whether multiple divine persons could assume one human nature (Article 6), and whether one divine person could assume multiple human natures (Article 7). Berquist uses these inquiries to examine the nature of divine personality, infinite power, and the logic of the hypostatic union, drawing parallels to the mystery of the Trinity while addressing potential logical contradictions and heresies.

17. Why the Son’s Incarnation is Most Fitting #

This lecture explores Question 3, Article 8 of Aquinas’s treatment of the Incarnation, examining why it was most suitable for the Son (rather than the Father or Holy Spirit) to become incarnate. Though all three divine persons could have assumed human nature, Berquist and Aquinas demonstrate the particular congruence between the Son’s role as the eternal Word and the Incarnation. The lecture also begins Question 4, asking whether human nature was more assumable than other natures.

18. The Incarnation: Nature, Person, and Assumption #

This lecture examines Thomas Aquinas’s treatment of the Incarnation, specifically whether the Son of God assumed a human person or merely human nature, and whether that nature could have been universal rather than individual. Berquist explores the distinction between nature and person through the lens of Thomistic metaphysics, using geometric analogies and carefully distinguishing different senses of key terms. The discussion clarifies how the divine person terminates the assumption of human nature while preserving the genuine individuality of Christ’s humanity.

19. Universal Causes, Predicables, and Wisdom in Aristotle #

This lecture explores the critical distinction between universale in predicando (universal predication) and universale in causando (universal causality), drawing on Aristotle’s conception of wisdom as the science of being and first causes. Berquist examines how Heidegger and Spinoza confuse these two senses of universality, contrasting their errors with Aristotle’s careful treatment in the Metaphysics, which maintains both dimensions without conflating them. The lecture demonstrates how this distinction applies to ethics, the incarnation, and the proper structure of philosophical knowledge.

20. Christ’s Assumption of Body and Soul #

This lecture examines Thomas Aquinas’s systematic refutation of heresies regarding Christ’s Incarnation, specifically addressing whether Christ assumed a true body (against Manichaeans who claimed a phantasm), an earthly body (against those claiming a celestial body), and a human soul (against Arians and Apollinarians). Berquist walks through Thomas’s three-fold reasoning for each article, showing how the truth of human nature, the efficacy of redemption, and divine dignity all demand that Christ assume the complete human composite of body and rational soul.

21. The Incarnation: The Assumption of Human Nature and Its Parts #

This lecture continues Thomas Aquinas’s systematic treatment of the Incarnation, focusing on why the Son of God assumed a complete human nature including body, soul, and intellect. Berquist examines three main objections (from the Manichaeans, Apollinarians, and various heretics) and explores the order in which these parts were assumed—distinguishing between temporal simultaneity and natural order by dignity and causality. The lecture emphasizes that true redemption requires the assumption of all human components and explains how the divine Word’s presence perfects rather than eliminates human nature.

22. The Assumption of Soul and Spirit in the Incarnation #

This lecture explores whether Christ assumed a human soul and rational intellect (spirit/mens), examining the metaphysical distinction between soul as the substantial form of the body and spirit as the higher rational powers. Berquist addresses how the Word of God relates to these aspects of human nature, refuting errors like Apollinarianism while establishing that complete human nature requires both soul and rational mind. The lecture also clarifies the order of assumption—whether temporal or according to nature—between spirit, soul, and flesh.

23. The Order of Assumption in the Incarnation #

This lecture examines the theological question of how the Son of God assumed human nature, focusing on the precise order and means of assumption. Berquist explores whether flesh was assumed through the soul, whether the soul was assumed through the spirit, and whether the whole human nature was assumed through its parts or vice versa. The lecture emphasizes the critical distinction between temporal order (simultaneity) and natural order (causality and dignity), using Aristotelian philosophy to clarify how the hypostatic union preserves both divine transcendence and authentic human nature.

24. Christ’s Nature, Grace, and the Heretical Objection #

This lecture addresses Father Dressler’s heretical claim that Christ cannot be God because no human being can be God, using logical analysis and philosophical distinctions to refute the objection. Berquist demonstrates how the distinction between human nature and human person (hypostasis) resolves the apparent contradiction, and then establishes why habitual grace must exist in Christ’s soul through three key reasons: his union with the Word, the nobility of his soul requiring elevation, and his role as mediator to humanity. The lecture also explores the philosophical problem of divine immutability and how God can ‘become’ man without undergoing change.

25. Virtues, Gifts, and Grace in Christ #

This lecture examines whether Christ possessed the virtues, theological virtues (faith and hope), and the gifts of the Holy Spirit. Berquist works through Thomas Aquinas’s systematic treatment of Christ’s perfections, distinguishing between what Christ possessed (all moral virtues, intellectual virtues, and the gifts of the Holy Spirit) and what he did not possess (faith and hope, which would be contrary to his state of beatitude). The discussion integrates Aristotelian virtue ethics with Christian theology to explain how grace produces virtues in the powers of the soul.

26. Grace, Virtues, Gifts, and Prophecy in Christ #

This lecture examines whether Christ possessed the gift of fear, gratuitously given grace (gratis data), and prophecy—exploring how these perfections relate to Christ’s dual nature as both God and man. Berquist works through Thomas Aquinas’s systematic treatment of objections and resolutions, emphasizing the distinction between defective virtues (faith, hope) and those that represent pure perfection (reverence, prophecy as knowledge of distant things). The lecture illustrates how Christ, as the first and chief teacher of faith, necessarily possesses all graces in fullness while also beginning discussion of the fullness of grace in Christ.

27. The Fullness and Infinity of Christ’s Grace #

This lecture addresses theological questions concerning the fullness of grace in Christ, arguing that Christ possesses grace uniquely in its perfection and extension. Berquist distinguishes between two modes of fullness—on the side of grace itself (private to Christ) and on the side of the subject (communicated to others)—and examines whether Christ’s grace can properly be called infinite, clarifying the difference between infinite being and infinite in notion.

28. Grace in Christ: Fullness, Infinity, and Growth #

This lecture continues the Thomistic examination of Christ’s grace, focusing on Articles 9-13 of Aquinas’s treatment. Berquist explores whether Christ possesses grace in its fullness, whether this fullness is unique to Christ, whether grace can be infinite, and whether Christ’s grace could increase. The lecture integrates metaphysical distinctions about form and subject with considerations of the hypostatic union, drawing parallels between mathematical and natural limits that prefigure modern physics.

29. Qualified Being, Knowledge, and Grace in Christ #

This lecture explores the philosophical distinction between qualified and unqualified being, drawing on Platonic and Socratic epistemology to clarify how we can know what we do not know. Berquist demonstrates these distinctions through examples of coming-to-be, counting, and knowing persons imperfectly. The discussion transitions to theological applications, particularly examining Christ’s habitual grace, its fullness, and its relationship to the union of human nature with the divine person, concluding with an analysis of how grace as a partaking of divine nature relates to divine wisdom and power.

30. Equivocation, Distinction of Senses, and Metaphorical Speech #

This lecture explores how confusion over the multiple senses of a word leads to logical fallacies and philosophical errors. Berquist demonstrates through concrete examples (whole/part, liberal, breathing/philosophizing) how Aristotle’s method of distinguishing word senses is essential for avoiding sophistical refutations. The lecture emphasizes that metaphorical speech requires careful attention to likeness rather than univocal meaning, illustrated through discussions of headship in natural and mystical bodies.

31. Christ as Head of the Church: Nature and Scope #

This lecture explores Christ’s role as head of the Church through Thomistic theology, examining whether Christ is head of both souls and bodies, whether his headship extends to all men across time, and whether angels fall under his headship. Berquist works through Thomas Aquinas’s systematic treatment of these questions, establishing the distinction between different grades of membership in the mystical body and clarifying how Christ’s personal grace and grace as head are identical in essence but differ in notion.

32. Christ’s Knowledge: Divine and Created #

This lecture concludes the discussion of Christ as head of the Church and the devil as head of the wicked, then transitions to Question 9 on Christ’s knowledge. Berquist examines why Christ must possess created knowledge in addition to his divine knowledge, drawing on Thomistic arguments for the perfection of Christ’s human soul and the necessity of knowledge for the proper operation of human nature.

33. Christ’s Multiple Kinds of Knowledge #

This lecture explores whether Christ possessed created knowledge in addition to his divine knowledge, examining four distinct types of knowledge in Christ’s human soul: divine, beatific, infused, and acquired knowledge. Berquist works through Thomas Aquinas’s treatment of how these different knowledges coexist without contradiction, particularly addressing objections that perfect knowledge would eliminate imperfect knowledge, and demonstrating why Christ’s assumption of perfect human nature requires the actualization of his human intellect through multiple modes of knowing.

34. Christ’s Acquired Knowledge and the Active Intellect #

This lecture examines whether Christ possessed acquired knowledge—knowledge gained through the operation of the active intellect upon sensory experience. Berquist follows Thomas Aquinas’s argument that Christ, having assumed complete human nature including both the possible and active intellect, must have possessed acquired knowledge. The lecture distinguishes three types of knowledge in Christ (beatific, infused, and acquired) and resolves the apparent redundancy by showing these are different modes of knowing the same object, using the analogy of sight and touch.

35. Christ’s Knowledge of the Divine Essence and All Things #

This lecture examines Thomas Aquinas’s treatment of Christ’s knowledge, specifically whether Christ’s soul comprehends the divine essence and whether Christ knows all things in the Word. Berquist carefully distinguishes between comprehension (knowing something as fully as it is knowable) and vision (seeing without comprehending), demonstrating that despite the hypostatic union, Christ’s human soul remains finite and cannot comprehend the infinite divine essence. The lecture also addresses the apparent problem of Mark 13:32 regarding Christ’s knowledge of the day of judgment, resolving it through the principle of non-revelation rather than non-knowledge.

36. Christ’s Knowledge of Infinite Things #

This lecture addresses whether Christ’s soul can know an infinity of things, exploring the nature of infinite knowledge and how a finite creature can comprehend what is infinite. Berquist systematically works through objections using Aristotelian and Thomistic distinctions, particularly the crucial distinction between what is infinite ‘simply’ (God) versus ‘according to something’ (creatures). The discussion centers on how Christ knows infinite things through infused knowledge without comprehending God’s infinite power.

37. Christ’s Infused Knowledge and Its Perfection #

This lecture examines the nature of infused knowledge in Christ’s soul—the supernatural knowledge divinely poured into Him that stands between natural human reasoning and the beatific vision. Berquist explores whether Christ knew all things through this knowledge, whether He required phantasms (images) to understand, and how this knowledge compares to angelic knowledge, drawing on Thomas Aquinas’s synthesis of Aristotelian epistemology with Christological theology.

38. Christ’s Knowledge: Discursive and Habitual Knowing #

This lecture examines whether Christ possessed discursive (reasoning) and habitual knowledge, addressing objections that such knowledge would be incompatible with His comprehensor status and infused knowledge. Berquist explores how Christ’s rational soul necessarily possesses the proper operations of reason, including the ability to move from one thing to another through discourse (colatio), while distinguishing between acquiring knowledge through discourse and using knowledge discursively. The lecture culminates in examining whether infused knowledge in Christ was habitual, establishing that Christ’s human knowledge operated according to human nature while perfected by supernatural gifts.

39. Christ’s Acquired Knowledge and the Agent Intellect #

This lecture examines Thomas Aquinas’s treatment of Christ’s acquired or experiential knowledge (scientia experimentalis), focusing on how Christ could know all things knowable to human nature despite not experiencing everything directly. Berquist explores the role of the agent intellect (intellectus agens) in abstracting universal forms from sensible images, explaining how knowledge can be acquired not only through direct experience but through rational discourse from one thing to another. The lecture addresses the apparent tension between Christ’s perfection and the seeming imperfection of acquired knowledge, distinguishing between Christ’s three kinds of knowledge: beatific, infused, and acquired.

40. Christ’s Knowledge, Learning, and Power #

This lecture examines three major questions about Christ’s human nature: whether Christ progressed in acquired knowledge despite possessing infused and beatific knowledge; whether Christ learned from men and angels; and whether Christ’s soul possessed omnipotence. Berquist walks through Thomas Aquinas’s careful distinctions between types of knowledge and power, showing how the Incarnation preserves the distinction of natures while explaining how Christ’s human soul operated within its natural limitations.

41. Christ’s Omnipotence and Bodily Defects #

This lecture examines whether Christ’s soul possessed omnipotence and explores the nature and necessity of Christ’s bodily defects through Questions 13 and 14 of the Tertia Pars. Berquist analyzes omnipotence in four dimensions—with respect to creatures generally, to miraculous changes, to Christ’s own body, and to the execution of his will—establishing crucial distinctions between Christ’s power according to his own nature versus his power as instrument of the Word. The lecture concludes by examining why Christ assumed bodily defects like death, hunger, and thirst as necessary for satisfaction, instruction in faith, and example of patience.

42. Christ’s Assumption of Bodily Defects and Natural Necessity #

This lecture explores Thomas Aquinas’s treatment of why and how Christ assumed bodily defects (death, hunger, thirst, pain) despite the perfection of his soul. Berquist examines the three reasons for this assumption (satisfaction for sin, proof of true humanity, and example of patience), the distinction between contracting and assuming defects, and the philosophical distinction between natural necessity and coercive necessity that allows Christ to be subject to human infirmities without loss of freedom.

43. Defects of the Soul in Christ: Sin, Inclination, and Ignorance #

This lecture examines Thomas Aquinas’s treatment of whether defects pertaining to Christ’s soul—particularly sin, the inclination to sin (fomes peccati), and ignorance—can be reconciled with Christ’s perfection and true humanity. Berquist walks through the first four articles of Question 15 of the Third Part of the Summa Theologiae, using careful metaphysical distinctions and scriptural interpretation to show why Christ could take on bodily defects for our redemption while remaining entirely free from moral and spiritual defects.

44. Christ’s Defects, Knowledge, and Passibility of Soul #

This lecture examines whether Christ appropriately assumed bodily and spiritual defects, how Christ possessed knowledge without ignorance, and how Christ’s soul could undergo passion. Berquist develops Thomas Aquinas’s treatment of why Christ assumed suffering, death, hunger, and thirst while remaining sinless and perfectly virtuous, and explores the distinction between true passions and the perfect virtue that characterized Christ’s emotional life.

45. Word, Logos, and the Problem of Translation #

This lecture explores the philosophical and theological challenges of translating key terms—particularly ’logos,’ ‘verbum,’ and ‘word’—across Greek, Latin, and English. Berquist examines how words shift meaning over time and how translation must either preserve original sense or adapt to accommodate linguistic change. The lecture uses the Gospel of John’s opening and contemporary issues of semantic drift to illustrate these problems.

46. Christ’s Passions: Sadness, Fear, Wonder, and Anger #

This lecture examines whether Christ experienced sadness, fear, wonder, and anger—key passions of the human soul. Berquist develops Thomas Aquinas’s distinction between full passions (which dominate reason) and pro-passions (which begin in the sensitive appetite but remain under the control of reason). The lecture explores how Christ, as fully human while remaining divine, could experience these emotions without them impairing his perfect knowledge and justice.

47. God Is Man: Predication and the Incarnation #

This lecture examines the first article of Question 16 of the Tertia Pars, asking whether the statement ‘God is a man’ is true. Berquist explores the apparent logical impossibility of this claim given the maximal distance between divine and human natures, then shows how Thomas Aquinas resolves the problem through careful analysis of concrete versus abstract predication and the role of suppositum (hypostasis). The lecture demonstrates how the incarnation does not violate logical principles but rather reveals a deeper understanding of how predication works when two distinct natures are united in a single supposita.

48. Predication in the Incarnation: God is Man, Man is God #

This lecture explores the logical and theological problem of how apparently contradictory predications can be true of Christ: that God is a man and that man is God. Berquist works through Thomas Aquinas’s treatment of these questions, focusing on the distinction between concrete and abstract names, the unity of hypostasis (person), and how the communication of idioms allows properties of one nature to be predicated of the person who possesses both natures. The lecture also addresses whether Christ can properly be called ‘Homo Dominicus’ (Lordly Man) and examines various logical fallacies that arise from misunderstanding predication.

49. Predication in the Incarnation: Divine and Human Natures #

This lecture examines how predicative statements about Christ’s divine and human natures can be properly true despite their metaphysical distinctness. Berquist explores the distinction between concrete names (God, man) and abstract names (divinity, humanity), the concept of hypostatic union as grounding unified predication, and the asymmetry between what can be said of divine versus human nature. The discussion addresses how Thomas Aquinas resolves apparent contradictions in patristic formulations, particularly Augustine’s retraction of ‘Homo Dominicus’ and the theological implications of statements like ‘God suffered’ or ‘man is God.’

50. Christological Predication: ‘God Was Made Man’ and ‘Man Was Made God’ #

This lecture examines Articles 6-7 of Thomas Aquinas’s treatment of the Incarnation, focusing on the logical and metaphysical problems of predicating ‘God was made man’ and ‘man was made God.’ Berquist explores how these statements can be true without implying that God comes into being or changes, using sophisticated distinctions between suppositum (person) and nature, absolute and relative predication, and simple versus qualified coming-to-be (simpliciter versus secundum quid). The lecture demonstrates how medieval logic and precise terminology resolve apparent theological contradictions.

51. Christ as Creature and the Problem of Precise Language #

This lecture addresses Articles 8-10 from Aquinas’s treatment of the Incarnation, focusing on whether Christ can be called a creature, whether the man Christ began to be, and the unity of Christ despite possessing two natures. Berquist emphasizes the crucial distinction between absolute and qualified (secundum quid) predication, warning of heretical misinterpretation when theological language is imprecise. The lecture explores the medieval logical framework of supposition theory to clarify how properties of human and divine natures are predicated of Christ as one suppositum.

52. The Unity of Christ: One Person or Two? #

This lecture examines the fundamental question of whether Christ should be considered one or two, given His possession of both divine and human natures. Berquist presents Augustine’s and other patristic arguments that Christ is ‘both God and man’ and therefore two, then develops Thomas Aquinas’s resolution: Christ is one person (suppositum/hypostasis) though He has two natures. The discussion centers on the distinction between nature and person, the rules of abstract versus concrete predication, and how truth lies between the extreme heresies that deny either the duality of natures or the unity of person.

53. The Unity and Existence of Christ #

This lecture examines the metaphysical foundations of Christ’s unity as one person in two natures, focusing on Questions 17 of the Summa Theologiae. Berquist explores how to properly speak of Christ using Aristotelian distinctions between hypostasis/suppositum (that which subsists) and nature (that by which something is), and addresses the critical theological problem of whether Christ has one or two existences (esse), using the analogy of the human soul and body to illuminate the hypostatic union.

54. Christ’s Will: Divine and Human in the Incarnation #

This lecture examines Question 18 of Thomas Aquinas’s treatment of the Incarnation, specifically whether Christ possesses one will or two wills. Berquist traces the historical heresies (Apollinarianism, Monophysitism, Monothelitism) that denied Christ’s human will, presents Thomas’s theological resolution that Christ must have both divine and human wills, and explores the relationship between the divine will as first mover and the human will as a perfection of human nature. The lecture also introduces the distinction between the rational will and sensual appetite (sense desire), examining how these relate to Christ’s perfect human nature.

55. Christ’s Will: Unity and Distinction in the Incarnation #

This lecture examines whether Christ possessed one will or two wills, analyzing the relationship between Christ’s divine and human wills through Thomistic theology and patristic sources. Berquist explores how Christ can have a truly human will while maintaining perfect unity with the divine will, addressing the distinction between will as power versus will as act, and clarifying how there can be no contrariety between Christ’s natural human appetites and his rational will conforming to God’s will.

56. Christ’s Wills: Natural, Sensual, and Rational #

This lecture examines whether Christ possessed one will or multiple wills, specifically exploring the distinction between the natural will (voluntas naturae), the sensual will of emotions (voluntas sensualitatis), and the rational will (voluntas rationis). Berquist works through Aquinas’s treatment of how Christ’s human wills—which naturally recoiled from suffering and death—were not in contrariety with his divine will, since they were not impeded by reason or divine purpose. The lecture clarifies that conformity to God’s will in Christ occurred through the rational will, even as natural human aversion to pain remained intact.

57. Christ’s Operations: Divine and Human in Unity #

This lecture explores the Thomistic resolution of how Christ, as one person with two natures, can have both unified and distinct operations. Berquist presents the classical arguments for one operation versus two operations, examines the principle of ordered agents (principal agent and instrument), and explains how the divine nature uses the human nature’s operation while maintaining the integrity of both natures. The lecture defends the orthodox position defined by the Council of Constantinople III against monophysite and monothelite errors.

58. Operations and Merit in Christ #

This lecture covers Thomas Aquinas’s treatment of Christ’s operations (Question 19) and subjection (Question 20) from the Tertia Pars. Berquist discusses whether Christ has one or many operations, how human operations are defined, whether Christ could merit something for himself and for others, and the nature of Christ’s subjection to the Father. Central to the discussion is the distinction between properly human operations (proceeding from reason and will) and other operations of the living soul, along with the principle that merit is more noble than receiving without merit, and how Christ’s merit extends to others through the mystical body.

59. Christ’s Subjection to the Father: Nature and Person #

This lecture examines whether Christ is subject to God the Father and whether Christ is subject to himself, focusing on the crucial distinction between subjection of the person versus subjection of the nature. Berquist walks through Thomas Aquinas’s analysis of three modes of subjection (according to grade of goodness, divine power, and obedience) and addresses objections from Cyril and John of Damascus, emphasizing the importance of qualification to avoid Arian heresy.

60. Prayer and Priesthood in Christ: Nature and Purpose #

This lecture examines whether prayer belongs to Christ despite His omnipotence and divine knowledge, exploring the metaphysical distinction between Christ’s divine and human wills. Berquist and Thomas Aquinas resolve the apparent paradox by showing that prayer, as an unfolding of the human will before God, necessarily belongs to Christ according to His human nature. The lecture also introduces the priesthood of Christ as the perfect mediation between God and humanity, establishing the foundation for understanding Christ as both priest and victim.

61. The Priesthood of Christ and Sacrificial Mediation #

This lecture examines whether Christ possesses the office of priest, addressing objections based on Christ’s superiority to angels, his descent from Judah rather than Levi, and his role as lawgiver. Berquist explores the nature of priesthood as mediation between God and people, discusses Christ as both priest and victim, and analyzes the three reasons humans require sacrifice: remission of sin, preservation in grace, and union with God.

62. Christ’s Priesthood: Expiation of Sins and Eternal Effects #

This lecture examines Article 3 and Article 4 of Aquinas’s treatment of Christ’s priesthood, focusing on whether the effect of Christ’s priesthood is the expiation of sins and whether this effect pertains only to others or also to Christ himself. Berquist works through the objections and Thomas’s responses, explaining the distinction between the stain of guilt (macula culpae) and the obligation of punishment (reatus poenae), and clarifying how Christ as the fountain of priesthood does not receive the effects of priesthood but communicates them to others.

63. Christ’s Eternal Priesthood and Divine Adoption #

This lecture addresses two major theological questions: whether Christ’s priesthood remains eternal despite the unrepeatable nature of His passion and death, and whether adoption properly belongs to God as a divine action. Berquist works through Thomas Aquinas’s distinctions between the offering of sacrifice and its consummation, and between the offering itself and its effects, to show how Christ’s priesthood is eternal through the permanent efficacy of His sacrifice. The lecture then transitions to Question 23 on divine adoption, establishing that adoption is God’s communication of His infinite goodness to creatures, admitting them to participation in His inheritance.

64. Adoption in God and Rational Creatures #

This lecture explores whether divine adoption belongs to God at all, whether it belongs to the whole Trinity or only to the Father, whether adoption is proper to rational creatures, and whether Christ as man is an adopted son. Through careful scholastic analysis, Berquist and Thomas Aquinas examine how adoptive sonship differs fundamentally from natural sonship while being a true participation in divine fatherhood through grace. The lecture emphasizes the critical distinction between person (hypostasis) and nature in understanding why Christ, though possessing human nature, cannot be called an adopted son.

65. Christ’s Predestination and Its Exemplarity #

This lecture examines whether predestination properly belongs to Christ, how Christ can be predestined according to His human nature, and the relationship between Christ’s predestination and human predestination. Berquist works through Thomas Aquinas’s treatment of these questions, exploring the grace of union, the distinction between predestination as eternal divine act versus temporal effect, and how Christ’s predestination serves as both exemplar and cause of our predestination.

66. The Adoration of Christ: Unity of Person and Multiplicity of Causes #

This lecture examines Thomas Aquinas’s treatment of whether Christ’s divinity and humanity should be adored by one adoration or two separate adorations (Question 25 of the Tertia Pars). Berquist explores the crucial distinction between the person (hypostasis) who is honored and the causes of honor, demonstrating how the Incarnation reverses the structure of the Trinity. The lecture establishes the framework of latria (worship due to God alone) versus dulia (veneration due to creatures) and applies these categories to Christ’s humanity, images, the cross, and relics.

67. Veneration of the Cross, Mary, Relics, and Christ as Mediator #

This lecture addresses whether the cross of Christ, the Blessed Virgin Mary, and the relics of saints should be adored or venerated, and how such veneration differs from idolatry or false worship. Berquist also explores whether Christ’s role as mediator between God and man is unique to him and whether it belongs to him according to his human or divine nature. The discussion centers on the Thomistic distinctions between latria (worship owed to God alone) and dulia (veneration owed to creatures), and how these categories apply to sacred objects, persons, and the incarnate Christ.

68. Mary’s Sanctification in the Womb and the Immaculate Conception #

This lecture explores the theological question of whether the Blessed Virgin Mary was sanctified before her birth from the womb, and examines the relationship between sanctification, animation (ensoulment), and original sin. Berquist presents Thomas Aquinas’s systematic treatment of this question through competing arguments and objections, culminating in discussion of Pope Pius IX’s 1854 definition of the Immaculate Conception (Ineffabilis Deus). The lecture addresses how Mary’s preservation from original sin relates to Christ’s universal redemptive mission.

69. Sanctification of the Blessed Virgin in the Womb #

This lecture examines whether and how the Blessed Virgin Mary was sanctified before her birth from the womb, focusing on the theological conditions required for sanctification. Berquist works through Thomas Aquinas’s treatment of this question, addressing the relationship between animation (infusion of the rational soul), the infusion of grace, and the removal of original sin, while clarifying papal teaching on the Immaculate Conception and distinguishing sanctification from immaculate conception.

70. Mary’s Sanctification, Sinlessness, Grace, and Virginal Conception #

This lecture covers Thomas Aquinas’s treatment of the Blessed Virgin Mary’s sanctification in the womb (Question 27, Articles 4-6) and the beginning of Question 28 on her virginity. Berquist examines whether Mary was preserved from all actual sin, how her grace relates to Christ’s as the source of grace, whether sanctification in the womb was unique to Mary, and whether she remained a virgin in conceiving Christ. The lecture addresses scriptural objections, patristic sources (particularly Augustine, Jerome, and Ambrose), and the Church’s definitive teaching through Pope Pius IX’s encyclical Ineffabilis Deus.

71. The Virgin Conception and Birth of Christ #

This lecture examines Thomas Aquinas’s treatment of Christ’s virgin conception and virginal birth, addressing the fittingness of these mysteries and refuting objections. Berquist explores four reasons why virgin conception was suitable, responds to scriptural objections concerning Christ’s brothers and Joseph’s fatherhood, and defends the doctrine that Mary remained a virgin in giving birth through miraculous divine power rather than properties of a glorified body.

72. Mary’s Virginity and Betrothal to Joseph #

This lecture addresses three major questions concerning the Blessed Virgin Mary: whether she remained a virgin after giving birth to Christ, whether she vowed virginity to God, and whether Christ ought to be born of one who was betrothed. Berquist systematically works through objections against perpetual virginity, explaining the meaning of scriptural terms like ‘before,’ ‘until,’ ‘firstborn,’ and ‘brothers.’ He also explores the nature of Mary’s vow of virginity and its compatibility with Old Testament law, drawing heavily on patristic authorities, especially Augustine and Jerome.

73. Mary and Joseph’s True Marriage: Form and Perfection #

This lecture examines whether Mary and Joseph entered into a true and valid marriage despite their mutual vow of chastity and the absence of carnal consummation. Berquist systematically addresses scriptural objections and patristic authorities to establish that marriage achieves its formal perfection through conjugal consent alone, while distinguishing this from the consummation that pertains to the second perfection of marriage ordered toward offspring and education.

74. The Annunciation: Necessity, Messenger, and Mode #

This lecture explores Thomas Aquinas’s treatment of the Annunciation through four central questions: whether it was necessary to announce the Incarnation to Mary, through whom the announcement should be made (why Gabriel specifically), in what mode or manner the announcement occurred, and what order the angel followed. Berquist examines the theological reasons for each aspect, integrating arguments from Augustine, Dionysius, Gregory, and other patristic sources to defend the fittingness (congruentia) of the Annunciation as it occurred.

75. The Annunciation: Mode, Order, and Wonder #

This lecture examines Thomas Aquinas’s treatment of the Annunciation, specifically addressing whether the angel should have appeared to Mary through bodily vision and whether the announcement proceeded in a suitable order. Berquist explores the three objections regarding vision types, the distinction between stupefaction and wonder (admiratio), and the three intentions of the angel in approaching Mary. The lecture integrates philosophical reflections on wonder as the beginning of philosophy, drawing on Plato and Aristotle.

76. Christ’s Flesh from Adam and Davidic Descent #

This lecture examines Thomas Aquinas’s treatment of whether Christ assumed flesh from Adam and the human race, and how Christ can be properly called “Son of David” despite the genealogical complications in Matthew and Luke. Berquist addresses objections regarding original sin, the apparent contradiction between Christ being “the second man from heaven” and taking human flesh, and reconciles the seemingly irreconcilable genealogies through careful distinctions about levirate marriage, legal paternity, and theological purposes of different evangelists.

77. The Genealogies of Christ and Numerical Symbolism #

This lecture examines the apparent discrepancies between Matthew’s and Luke’s genealogies of Christ, explaining how Matthew emphasizes Christ’s kingly dignity through descent while Luke emphasizes priestly character through ascent. Berquist explores Augustine and Thomas’s interpretation of symbolic numerology (40, 42, 77, 12) as valid theological meanings alongside literal genealogical facts, and discusses how the Church Fathers were compelled to develop sophisticated theological responses to defend Scripture against heretical challenges.

78. The Incarnation: Matter, Genealogy, and Original Sin #

This lecture examines fundamental questions about the Incarnation, particularly whether Christ’s flesh was taken from the human race through Adam and how his conception relates to original sin. Berquist explores the genealogies of Christ in Matthew and Luke, the material composition of Christ’s body from the Virgin’s blood, and how Christ can be said to be “in” the patriarchs without contracting original sin. The discussion demonstrates how Christ assumed human nature while remaining free from sin and corruption.

79. Christ’s Conception and the Active Principle of the Holy Spirit #

This lecture examines Thomas Aquinas’s theology of Christ’s conception, focusing on whether the Holy Spirit should be attributed as the active principle of the incarnation. Berquist explores the distinction between the work being common to the Trinity while being appropriated to the Holy Spirit, the preposition ‘of’ (de) in ‘conceived of the Holy Spirit,’ and addresses objections regarding the proper causality involved. The lecture also discusses whether Christ should be said to be ’tithed’ in Abraham and the implications for understanding Christ’s relationship to original sin.

80. The Virgin Mary’s Role in Christ’s Conception #

This lecture examines whether the Blessed Virgin Mary played an active role in the conception of Christ’s body, focusing on the distinction between active and passive generative powers in males and females. Berquist works through Thomas Aquinas’s Article 4 of Question 32, addressing objections from Damascene and Augustine regarding whether Mary should be called the ‘father’ of Christ and clarifying the unique nature of Christ’s conception compared to ordinary human generation.

81. The Formation and Animation of Christ’s Body in the Womb #

This lecture examines Thomas Aquinas’s treatment of the Incarnation, specifically whether Christ’s body was perfectly formed and animated in the first instant of conception. Berquist explores the philosophical paradoxes involved in the transition of matter (blood to flesh), the role of the Holy Spirit’s infinite power, and how Christ’s case differs from ordinary human generation. The lecture demonstrates how fundamental principles from Aristotelian natural philosophy—particularly the distinction between perfect and imperfect acts, and between locomotion, formation, and growth—are essential for resolving theological questions about the Incarnation.

82. Christ’s Sanctification and Perfection from Conception #

This lecture examines whether Christ possessed sanctifying grace, free will, and the beatific vision in the first instant of his conception. Berquist works through Thomas Aquinas’s treatment of these questions (Q. 34, Articles 1-2), analyzing how Christ’s immediate union with the divine Word differs fundamentally from the gradual spiritual development of other creatures. The discussion centers on the distinction between perfect and imperfect operations, the meaning of sanctification, and how Christ could exercise free will and merit without prior deliberation.

83. Birth as Nature or Person: Christ’s Temporal and Eternal Nativity #

This lecture examines whether birth (nativity) belongs properly to nature or to the person/hypostasis, with particular focus on Christ’s two births—the eternal birth from God the Father and the temporal birth from the Virgin Mary. Berquist works through Thomas Aquinas’s metaphysical distinctions to clarify how birth as subject belongs to the person while birth as term belongs to nature, and explores the implications for understanding Mary as the Mother of God.

84. Christ’s Two Births and Mary as Mother of God #

This lecture explores the theological paradox of Christ’s two births—one eternal from God the Father and one temporal from the Virgin Mary—and resolves the apparent contradiction through distinctions between nature, person, and hypostasis. Berquist examines whether the Blessed Virgin can truly be called the Mother of God, defending this title against Nestorian objections and clarifying how Christ possesses one real sonship (eternal) while being understood to have two sonships according to reason (eternal and temporal). The lecture addresses fundamental questions about nativity, personhood, and the relations involved in the Incarnation.

85. Christ’s Birth: Relations, Manifestation, and Divine Wisdom #

This lecture covers questions 35-36 from the Summa Theologiae regarding Christ’s nativity, focusing on the metaphysics of relations (real vs. relations of reason), the painless birth of the Virgin Mary, the theological significance of Bethlehem as Christ’s birthplace, the suitable time of Christ’s incarnation during the Pax Romana, and whether Christ’s birth should have been universally manifested. Berquist emphasizes how Thomas applies Aristotelian metaphysics to Christological doctrine, particularly the principle that relations are multiplied by their causes rather than their terms.

86. The Manifestation of Christ’s Birth: To Whom and Why #

This lecture examines Thomas Aquinas’s treatment of whether Christ’s birth should have been made known to all people, some people, or none. Berquist explores the theological problem of reconciling Christ’s coming as Savior of all with the necessity of faith, which requires hiddenness. The lecture analyzes why selective manifestation to different recipients (shepherds, Magi, Simeon and Anna) represents the divinely ordered distribution of salvific knowledge.

87. The Manifestation of Christ’s Birth to Angels and Stars #

Berquist examines Thomas Aquinas’s treatment of Question 36, Article 5 of the Summa Theologiae concerning whether Christ’s birth ought to be manifested through angels and through a star. The lecture explores the theological rationale for different modes of revelation suited to different audiences—angels for Jews accustomed to angelic apparitions, and a star for Gentile astronomers—while addressing objections about why sensible signs were necessary and appropriate for revealing the Incarnation.

88. The Star of the Magi and the Manifestation of Christ #

This lecture examines the nature and properties of the star that appeared to the Magi, arguing that it was not a celestial star but a newly created supernatural sign. Berquist presents Thomas Aquinas’s analysis of why the star’s miraculous behavior—its directional movement, daytime visibility, intermittence, and descent to a specific house—proves divine agency rather than natural astronomical phenomena. The discussion also addresses why the Magi suitably adored Christ and offered gifts despite his apparent lack of royal dignity, showing how they were inspired by the Holy Spirit to recognize him as a celestial king.

89. Christ’s Circumcision, Naming, and Presentation in the Temple #

This lecture covers Questions 37-38 from Aquinas’s Summa Theologiae, examining Christ’s circumcision, the imposition of the name Jesus, and his presentation in the temple as key events in Christ’s entry into the world. Berquist explores why Christ underwent these Jewish observances despite having no original sin, how the name Jesus encompasses all prophetic names of the Messiah, and the theological significance of Mary’s purification and the offering of doves. The lecture demonstrates how Christ both fulfilled Old Testament figures and provided exemplary obedience to the law.

90. Christ’s Presentation in the Temple and John’s Baptism #

This lecture examines two key events in Christ’s early life: his presentation in the temple (covering the fulfillment of Old Law precepts regarding firstborn sons and maternal purification) and John the Baptist’s role in preparing for Christ through baptism. Berquist works through Thomas Aquinas’s systematic treatment of objections concerning why these events were necessary, particularly addressing how Christ could fulfill laws he was not bound by, and how John’s baptism—though not a sacrament—was suitable and divinely ordained.

91. John the Baptist’s Baptism: Divine Institution and Preparatory Grace #

This lecture examines Thomas Aquinas’s analysis of John the Baptist’s baptism through systematic theological argumentation. Berquist explores whether John’s baptism was divinely instituted, whether it conferred grace, who was suitable to receive it, and why those baptized by John required rebaptism in Christ. The discussion demonstrates how John’s baptism functioned as a preparatory sacramental rather than a true sacrament, preparing souls for Christ through teaching, habituation to the rite, and inducement to penance.

92. John’s Baptism and the Cessation of His Ministry #

This lecture examines Thomas Aquinas’s treatment of two critical questions: whether John’s baptism should have ceased immediately after Christ’s baptism, and whether those baptized by John required rebaptism by Christ. Berquist walks through Aquinas’s distinction between John’s preparatory baptism (a sacramental, not a sacrament) and Christ’s baptism as a true sacrament conferring grace and the Holy Spirit, addressing objections from Scripture and patristic sources while exploring the anthropological reality of human resistance to spiritual change.

93. Christ’s Baptism: Suitability, Necessity, and Timing #

This lecture examines Thomas Aquinas’s treatment of Christ’s baptism through three key articles: whether baptism was suitable for Christ, whether John’s baptism specifically was appropriate, and why age thirty was the fitting time. Berquist explores how Christ’s sinless nature paradoxically makes his baptism necessary—not for his own cleansing but for sanctifying the waters and providing exemplary obedience. The discussion synthesizes patristic sources (Ambrose, Chrysostom, Augustine, Gregory Nazianzen) with Aristotelian principles of causality and perfection.

94. Christ’s Baptism in the Jordan and the Opening of Heaven #

This lecture examines Thomas Aquinas’s theological justification for why Christ was baptized specifically in the Jordan River rather than the Red Sea, and why the heavens opened during this event. Berquist explores the typological significance of the Jordan as prefiguring entrance into the celestial kingdom, contrasts it with the Red Sea’s prefiguration of sin remission, and explains the three-fold spiritual meaning of the heavens opening. The discussion demonstrates how Thomistic theology uses patristic sources to interpret Scripture and employs the principle of appropriation to reveal divine mysteries.

95. The Holy Spirit’s Descent at Christ’s Baptism #

Berquist examines why the Holy Spirit descended visibly upon Christ at His baptism, despite Christ already possessing the fullness of grace from conception. The lecture explores the dove as the symbolic form of the Holy Spirit’s appearance, explaining how Christ’s baptism serves as an exemplar for all Christian baptisms and how the dove’s natural properties signify both the seven gifts of the Holy Spirit and the effects of baptism. The discussion includes the distinction between the Holy Spirit’s visible appearance and His invisible nature, the difference between the Son’s incarnation and the Spirit’s manifestation, and why the Father’s voice testified to the Son at this moment.

96. Christ’s Public Life and Way of Living #

This lecture examines whether Christ should have lived a solitary life or engaged publicly with others, grounded in Thomas Aquinas’s treatment of Christ’s way of life (conversatio) in the Summa Theologiae. Berquist analyzes three foundational purposes of the Incarnation—making truth known, liberating men from sin, and giving confidence to approach God—and argues that Christ’s public, active life of preaching represents the highest form of perfection, exemplified by the Dominican principle of contemplata aliis tradere (handing on to others the fruits of contemplation).

97. Christ’s Life: Austerity, Poverty, and Common Living #

This lecture examines three key aspects of Christ’s manner of living according to Thomas Aquinas: whether Christ should have led an austere life in food and drink, whether he should have lived in poverty, and how these choices relate to his office of preaching and the purposes of the Incarnation. Berquist explores the theological reasoning behind Christ’s conformity to common life while also demonstrating both fasting and participation in meals, his voluntary poverty as fitting to his preaching mission, and the symbolic significance of these choices for Christian living.

98. Christ’s Observance of the Law and Temptation in the Desert #

This lecture explores two major Thomistic questions: whether Christ properly observed the Old Testament law despite apparent violations of the Sabbath and dietary precepts, and whether Christ’s temptation in the desert was fitting and necessary for human salvation. Berquist examines the theological purposes of Christ’s law-observance and the four reasons why temptation was suitable, focusing on how Christ overcame the devil through justice rather than power and provided both aid and example for Christians facing temptation.

99. Christ’s Temptations and the Order of Temptation #

This lecture examines Thomas Aquinas’s analysis of Christ’s temptations in the desert, focusing on why the temptations occurred after a 40-day fast and in what order they were presented. Berquist explores the theological reasoning behind the sequence of temptations (gluttony, vainglory, avarice) and defends the historical and theological coherence of the Gospel accounts against various objections, demonstrating how the devil tempts progressively from lesser to graver sins.

100. Christ’s Teaching: To Jews First, Then Gentiles #

This lecture examines Thomas Aquinas’s theological explanation for why Christ limited his direct teaching to the Jewish people during his earthly ministry, reserving the preaching to Gentiles for the apostles after the Resurrection. Through four key reasons—fulfillment of Old Testament promises, demonstration of divine order, removal of occasion for Jewish complaint, and Christ’s merited authority through the cross—Berquist explores how Christ’s pedagogical method reflects God’s wisdom and the proper ordering of creation. The lecture demonstrates faith seeking understanding (fides quaerens intellectum) by moving from scriptural narrative to theological rationale.

101. Christ’s Public Teaching, Offense, and the Use of Parables #

This lecture explores three interconnected questions about Christ’s pedagogy: whether Christ should have preached publicly to the Jews without offending the Pharisees, and whether his teaching should have been entirely public or partially hidden through parables and private instruction to disciples. Berquist works through Thomas Aquinas’s analysis of how truth must sometimes be proclaimed despite causing scandal, how teaching can be hidden in different ways, and how parables serve as an accommodation to human capacity while stimulating imagination and wonder.

102. Christ’s Teaching: Written vs. Spoken Word #

This lecture examines the fourth article of a Thomistic treatment on Christ’s teaching, specifically why Christ did not commit His doctrine to writing despite the precedent of the Old Law written in stone. Berquist explores Thomas Aquinas’s argument that the spoken word is a more excellent and perfect tool of teaching than the written word, and that Christ’s teaching was properly conveyed through His apostles as members of His mystical body. The lecture also introduces the subsequent treatment of Christ’s miracles in general, establishing why miracles were suitable for confirming His teaching and manifesting God’s presence through grace.

103. Christ’s Miracles: Divine Power and Their Sufficiency #

This lecture examines whether Christ performed miracles by divine power, when He began performing miracles, and whether His miracles were sufficient to demonstrate His divinity. Berquist works through Thomas Aquinas’s treatment of these questions, addressing objections from Scripture and resolving apparent tensions between Christ’s omnipotence and His reported inability to perform miracles in His own country, His practice of prayer before miracles, and the fact that others also performed miracles.

104. Christ’s Miracles Concerning Spiritual Substances and Celestial Bodies #

This lecture examines the suitability of Christ’s miracles involving demons and celestial bodies, drawing primarily from Thomas Aquinas’s Summa Theologiae Question 44. Berquist addresses objections to why Christ performed exorcisms despite the strategic importance of concealing His divinity from demons, and defends the miraculous darkening at the Passion as a demonstration of divine power over the celestial order. The discussion integrates Patristic sources (especially Dionysius the Areopagite, Augustine, Jerome, and Chrysostom) with Aristotelian natural philosophy to reconcile miracles with the nature of created things.

105. Christ’s Miracles Concerning Men and Creatures #

This lecture examines Thomas Aquinas’s treatment of Christ’s miracles in Question 44, Articles 3-4 of the Summa Theologiae. Berquist explores why it was suitable for Christ to perform miracles concerning both the souls and bodies of men, addressing objections about the gradual nature of some healings, the connection between bodily and spiritual cure, and the logic of commanding secrecy about miracles. The lecture then considers miracles performed on irrational creatures and natural elements, arguing that such miracles demonstrate Christ’s universal dominion over all creation while remaining proportionate to his mission of salvation and peace.

106. Christ’s Transfiguration: Suitability, Glory, and Witnesses #

This lecture examines the theological significance and philosophical coherence of Christ’s transfiguration through four main questions: whether transfiguration was suitable for Christ, whether the clarity displayed was the clarity of glory, who the suitable witnesses were, and whether the Father’s voice was appropriate testimony. Berquist works through Thomas Aquinas’s treatment of these questions, emphasizing the distinction between substance and accident, the nature of figure and clarity as surface qualities, and the role of transfiguration in revealing to the disciples the glorious end toward which the difficult path of passion leads.

107. Logical Fallacies in Understanding the Incarnation #

This lecture examines the sophistical argument that if God became man and the Holy Spirit is God, then the Holy Spirit became man. Berquist identifies the error as the fallacy of accident rather than equivocation, and explains how this error arises from confusing the hypostatic union (which occurs in the person, not the nature) with properties of the divine nature. The lecture introduces the critical distinction between what a word means versus what it stands for in a speaker’s meaning, and applies this to understanding theological language about the Incarnation.

108. The Necessity of Christ’s Passion and Redemption #

This lecture examines whether it was necessary for Christ to suffer for human liberation, focusing on Thomas Aquinas’s analysis of necessity in different senses. Berquist clarifies that the Passion was not necessary by absolute necessity or force, but rather necessary from the supposition of God’s foreknowledge and will. The lecture explores how divine omnipotence, human freedom, and the Passion’s necessity are reconciled, and introduces the structure of Thomas’s systematic treatment of the Passion through twelve specific questions.

109. The Passion of Christ: Necessity and Suitability #

This lecture explores Thomas Aquinas’s analysis of why Christ’s passion was necessary for human redemption and why crucifixion was the most suitable means of liberation. Berquist works through the distinction between absolute necessity and necessity from supposition, examines whether alternative modes of redemption were possible, and presents seven reasons why the cross specifically demonstrates divine wisdom. The discussion integrates scriptural testimony with patristic commentary and philosophical reasoning.

110. Whether Christ Suffered All Human Passions and Pains #

This lecture explores Thomas Aquinas’s analysis of whether Christ underwent all human passions and whether His suffering was the greatest pain. Berquist works through the fifth and sixth questions of the Summa’s treatment of Christ’s passion, examining the distinction between species and genus of suffering, the causes and magnitude of Christ’s pain, and how Christ’s superior sensitivity and voluntary assumption of suffering intensified rather than diminished His suffering.

111. The Soul’s Suffering and the Beatific Vision in Christ #

This lecture examines whether Christ suffered according to his whole soul and explores the apparent paradox of Christ experiencing both the beatific vision and intense suffering simultaneously. Berquist analyzes Thomas Aquinas’s distinctions between suffering according to the soul’s essence versus its powers, and how the soul as form of the body can undergo passion even though some powers like the intellect are not acts of the body. The discussion clarifies how Christ prevented the natural ‘redundancy’ or overflow of passion from lower to higher powers, allowing perfect joy in the superior reason while the soul’s essence suffered from bodily torment.

112. Christ’s Soul, Passion, and the Paschal Timing #

This lecture addresses two central questions in Christology: whether Christ’s soul enjoyed the beatific vision while suffering during the Passion, and whether Christ suffered at a suitable time. Berquist employs Thomistic distinctions between the essence and powers of the soul to resolve the apparent contradiction between suffering and joy, and harmonizes scriptural accounts of the Passover timing and crucifixion hour using patristic and medieval theological sources.

113. The Efficient Cause of Christ’s Passion #

This lecture examines Question 47 of Aquinas’s treatment of Christ’s passion, focusing on the efficient cause of Christ’s death. Berquist explores how Christ was both killed by others (the persecutors as direct agents) and voluntarily laid down his life (as an indirect cause by not impeding his own death). The discussion centers on understanding the distinction between direct and indirect causation, the voluntary nature of Christ’s death despite violent infliction, and how Christ retained power over his body even unto death.

114. Voluntary Submission and the Passion of Christ #

This lecture examines the nature of Christ’s passion through the lens of Thomistic theology, focusing on how Christ’s suffering was both voluntarily embraced and externally inflicted. Berquist explores the relationship between obedience and charity in Christ’s passion, the role of the Father in handing over Christ, and the culpability of those who participated in the crucifixion. The discussion centers on reconciling apparent tensions: how Christ can be said to have killed himself while also being killed by others, and how obedience to the Father and love for humanity both motivate the passion.

115. Merit, Satisfaction, and Sacrifice in Christ’s Passion #

This lecture examines how Christ’s Passion operates as a cause of our salvation through four distinct modes: merit, satisfaction, sacrifice, and redemption. Berquist develops Thomas Aquinas’s teaching on how the Passion, while having its source externally in the persecutors, becomes meritorious through Christ’s voluntary acceptance, constitutes superabundant satisfaction for all sins through the dignity of his person, functions as a true sacrifice reconciling humanity to God, and serves as the price of our redemption from slavery to sin and obligation to punishment.

116. Christ’s Redemption: Modes and Effects of the Passion #

This lecture examines whether Christ’s Passion works salvation through redemption, exploring the relationship between God’s ownership of man, the devil’s unjust claim, and Christ’s satisfactory payment. Berquist works through Thomas Aquinas’s treatment of redemption as liberation from both the slavery of sin and the obligation of punishment, clarifying how Christ redeems us by his blood without that blood being paid to the devil but rather to God as the supreme judge.

117. The Effects of Christ’s Passion: Liberation from Sin, Devil, and Punishment #

This lecture examines three primary effects of Christ’s Passion through articles 1-3 of Question 49 of Thomas Aquinas’s Summa Theologiae. Berquist explores how the Passion causes remission of sins through three modes (provoking charity, redemption through the mystical body, and as instrument of divinity), how it liberates humanity from the devil’s power despite God’s continued permission for temptation, and how it removes the obligation for punishment while still allowing for penance as configuration to Christ’s suffering.

118. Christ’s Passion: Reconciliation, Heaven’s Gate, and Exaltation #

This lecture examines Thomas Aquinas’s treatment of how Christ’s passion effects reconciliation with God, opens the gate of heaven, and merits Christ’s own exaltation. Berquist works through objections and resolutions regarding whether God’s eternal love makes reconciliation necessary, how the wicked act of killing Christ can reconcile us, how entrance to heaven was possible before the passion, and how Christ could merit exaltation through suffering. The discussion integrates scriptural authority, metaphysical reasoning about causality and merit, and philosophical analysis of divine simplicity and perfection.

119. The Suitability and Effects of Christ’s Death #

This lecture examines Thomas Aquinas’s treatment of whether it was fitting for Christ to die, focusing on the five principal reasons Thomas provides: satisfaction for sin, manifestation of true humanity, liberation from fear of death, example of spiritual dying, and demonstration of power over death with hope of resurrection. Berquist explores how Christ’s death as a man is compatible with His identity as the fountain of life according to His divinity, and discusses the permanence of the hypostatic union even through the separation of body and soul in death.

120. The Hypostatic Union and Christ’s Death #

This lecture examines whether Christ’s divinity separated from his flesh and soul at death, arguing that the hypostatic union remained unbroken throughout. Berquist works through Thomas Aquinas’s responses to objections concerning the nature of Christ’s death, the permanence of the divine-human union, and whether Christ remained a man during the three days in the tomb.

121. Christ’s Incorruptibility, Duration in the Tomb, and Descent to Hell #

This lecture examines three interconnected mysteries of Christ’s passion: why His body remained incorrupt in the sepulcher despite undergoing death, how the duration of one day and two nights should be understood through the figure of synecdoche, and why Christ’s descent to hell was a fitting completion of His redemptive work. Berquist presents Thomistic arguments distinguishing between different regions of hell and explaining how Christ’s presence and power affected the saints, the damned, and those in purgatory differently.

122. Christ’s Descent to Hell: Person, Nature, and Liberation #

This lecture examines Thomas Aquinas’s treatment of Christ’s descent into hell, focusing on the theological distinction between divine person (hypostasis) and human nature. Berquist explores how the whole Christ could be present in hell despite bodily separation, the necessity of Christ remaining in hell for three days, and the liberation of the Old Testament saints from the deprivation of the beatific vision. The discussion demonstrates how grammatical categories (masculine vs. neutral gender, substantive vs. adjective) illuminate theological truths about the incarnate Word.

123. Christ’s Resurrection: Necessity and Causes #

This lecture examines Thomas Aquinas’s treatment of why Christ’s resurrection was necessary, exploring five theological reasons grounded in divine justice, faith, hope, salvation, and the manifestation of divine power. Berquist works through the objections systematically, clarifying how the resurrection completes Christ’s redemptive work by bestowing positive goods upon humanity, distinct from the passion’s work of removing evil.

124. Christ’s Resurrection: Suitability, Timing, and Nature of the Risen Body #

This lecture examines the theological appropriateness of Christ’s resurrection on the third day, addressing objections about timing and the conformity of members to their head. Berquist explores why an interval between death and resurrection was necessary to demonstrate the truth of both events, how the third day signifies mystical perfection, and introduces the question of whether Christ possessed a true human body after resurrection. The discussion harmonizes scriptural accounts and draws on Thomistic theology to resolve apparent contradictions in the Gospel narratives.

125. The Glorious and Integral Body of the Risen Christ #

This lecture examines the qualities and properties of Christ’s risen body through Thomas Aquinas’s systematic treatment of objections. Berquist addresses whether Christ’s body was glorious, whether it retained integrity (including flesh and blood), and how the apparently contradictory Gospel accounts (tangibility, eating, passing through doors) cohere with the doctrine of a glorified, incorruptible body. The lecture demonstrates how divine power preserves the true nature of the human body while removing the conditions of corruptibility.

126. The Resurrection of Christ: Manifestation and Wounds #

This lecture explores the manifestation of Christ’s resurrection and the theological significance of his retained wounds. Berquist examines why the resurrection was revealed only to specific witnesses rather than all people, why the disciples did not witness the actual rising, and why Christ’s resurrected body bore permanent scars. The discussion integrates Thomistic theology with patristic sources to address apparent scriptural contradictions regarding the timing and nature of Christ’s appearances.

127. Christ’s Resurrection: Appearances, Forms, and Arguments #

This lecture explores the post-resurrection appearances of Christ to his disciples, examining whether he appeared in his true form or in altered appearances, and whether he proved the resurrection through philosophical arguments or evident signs. Berquist discusses how Christ’s manifestations adapted to the spiritual dispositions of the disciples, distinguishing between figurative manifestation and deception, and argues that the signs Christ presented were sufficient to establish both the truth and glory of the resurrection.

128. Christ’s Resurrection as Cause of Our Resurrection #

This lecture examines whether Christ’s resurrection is a cause of our bodily and spiritual resurrection, and what kind of cause it is. Berquist works through Thomas Aquinas’s treatment of this question, distinguishing between primary and secondary causation, efficient and exemplary causality, and resolving apparent contradictions between divine justice and Christ’s instrumental role. The lecture covers both the resurrection of bodies and souls, clarifying how Christ’s resurrection extends to all persons though exemplarily only to the justified.

129. The Ascension of Christ: Suitability, Nature, and Power #

This lecture examines St. Thomas Aquinas’s treatment of Christ’s ascension through six key questions: whether ascension was suitable for Christ, according to which nature it belonged to him, whether he ascended by his own power, whether he ascended above all bodily heavens, whether above all spiritual creatures, and what effects the ascension produces. Berquist works through Thomistic arguments addressing apparent contradictions between Christ’s perfect state (which should require no motion) and the scriptural account of his ascension, ultimately establishing that ascension belongs to Christ’s human nature while being caused by divine power, and that it produces supernatural effects in the faithful through strengthening faith, hope, and charity.

130. Christ’s Ascension: Power, Place, and Salvation #

This lecture explores Thomas Aquinas’s treatment of Christ’s ascension into heaven, examining whether the ascension was suitable for Christ, whether it occurred by his own power, whether he ascended above all heavens and spiritual creatures, and how the ascension functions as a cause of human salvation. The discussion integrates Aristotelian natural philosophy with theological reasoning, particularly addressing how a glorified body can move upward contrary to the natural downward motion of earthly bodies, and how Christ’s dignity through hypostatic union transcends even spiritual creatures.

131. The Session of Christ at the Right of the Father #

This lecture examines the Thomistic doctrine of Christ’s session (sitting) at the right hand of God the Father following his ascension. Through four articles of theological inquiry, Berquist and Thomas Aquinas investigate whether this session is literal or metaphorical, whether it belongs to Christ’s divine nature, human nature, or both, and whether it is exclusive to Christ or shared with other creatures. The lecture demonstrates how Thomas resolves apparent scriptural contradictions through careful distinctions between bodily and metaphorical meaning, and between the condition of nature and the unity of the suppositum (person).

132. Christ’s Judicial Power: Nature, Attribution, and Universality #

This lecture examines the judicial power of Christ across six key questions: whether judicial power belongs to Christ, whether it pertains to him according to his human or divine nature, whether he merited this power, whether his judgment extends universally to all human affairs, and the necessity of a final judgment. Berquist follows Thomas Aquinas’s systematic treatment, exploring how judicial power is appropriated to the Son as eternal Wisdom and Truth, how Christ’s human nature participates in this divine prerogative through grace and merit, and how his judgment encompasses all creation while respecting both divine transcendence and human compassion.

133. The Necessity of Final Judgment and Christ’s Judicial Power over Angels #

This lecture examines why a final universal judgment is necessary despite the immediate judgment of souls after death, and whether Christ’s judicial power extends to the angels. Berquist works through objections to both doctrines using Thomistic reasoning, arguing that a perfect judgment requires the consummation of all changeable things, and that Christ possesses judicial authority over angels through both his divine nature and his human nature assumed in the Incarnation.