Lecture 17

17. Why the Son's Incarnation is Most Fitting

Summary
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.

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Lecture Notes

Main Topics #

The Question of Fittingness #

  • Central Issue: Why the Son rather than Father or Holy Spirit, given that all three possess infinite power?
  • This is a question of appropriateness (convenientia) and fittingness, not absolute necessity
  • All previous articles established that Father and Holy Spirit could become incarnate; this article explains why the Son’s incarnation is most suitable
  • The structure makes the question relevant: once we accept possibility, we ask why this particular arrangement is fitting

Objections Raised Against the Son’s Incarnation #

In favor of the Father:

  • Through incarnation of the Father, men would gain true knowledge of God (John 18:37)
  • If the Son became incarnate, confusion arose (Arius mistakenly thought “Father is greater than me” applied to divine nature)
  • Creation is appropriated to the Father, so re-creation through incarnation should belong to Father

In favor of the Holy Spirit:

  • Incarnation is ordered to remission of sins (Matthew 1:21)
  • Remission of sins is attributed to the Holy Spirit (John 20:22-23)
  • Therefore the Holy Spirit’s incarnation seems more fitting

Key Arguments for the Son’s Incarnation #

First Reason: From the Union Itself #

Congruence through the Word as Exemplar:

  • The Logos (Word of God) stands in a unique relation to all creation
  • Just as an artist’s thought/concept is the exemplar of what the artist makes, God’s eternal thought (the Word) is the exemplar of all creatures
  • Creatures are established in their own species by participating in this divine likeness
  • Therefore, when creatures need restoration/repair, it is fitting that the Word (through whom they were made) unite to restore them
  • The artist repairs by applying the same form through which he originally created

Special Congruence with Human Nature:

  • The Word is the concept of eternal wisdom
  • All human wisdom is derived from participation in the divine Word
  • Man perfects himself (as a rational creature) by advancing in wisdom through partaking of the Word
  • The Greek term Logos means both ‘Word’ and ‘reason’
  • Man is defined as the rational animal—his essence is reason
  • Therefore there exists an inherent affinity between what makes man human (reason/Logos) and the divine person called the Logos
  • Man is most himself through his thoughts, and this Word is the thought of God

Man as Microcosm:

  • Creation contains both spiritual/immaterial creatures (angels) and material world
  • Man unites both dimensions (spiritual soul and material body)
  • Therefore it is appropriate that God unite himself to man, who unites the whole of creation back to God

Second Reason: From the End/Purpose of Incarnation #

Adoptive Sonship:

  • The purpose of incarnation is the fulfillment/predestination of those ordered to celestial inheritance
  • Such inheritance belongs only to sons (Romans 8:17: “sons and heirs”)
  • Men are called to become adopted sons of God
  • Therefore it is fitting that the one who is the natural Son become incarnate, so that men might partake of sonship through him
  • This reflects Romans 8:29: men are “predestined to be conformed to the image of his Son”
  • The Son becomes man so that men might become sons

Third Reason: From the Nature of Original Sin #

The Sin of Disordered Knowledge:

  • The first man sinned not through fleshly desire but through disordered desire for knowledge (Genesis 3: “you will be as God, knowing good and evil”)
  • This was a spiritual sin, not a sin of flesh
  • Therefore it is fitting that man be led back to God through the Word of true wisdom
  • The remedy corresponds to the wound: sinful pride in forbidden knowledge is reversed by the incarnation of divine Wisdom itself

Reversal of the Fall:

  • The fall began with woman (Eve) and was consummated with man (Adam)
  • Therefore proper redemption begins with a woman (Mary) and proceeds to man (the second Adam)
  • Mary’s fiat (consent) reverses Eve’s disobedience

Response to Objections #

Against the Father’s Incarnation:

  • While true knowledge comes through the incarnation, nothing prevents human malice from abusing even God’s goodness to create error (Romans 2:4)
  • If the Father became incarnate, men could mistakenly think the Son insufficient for repair of human nature
  • This is an accidental, not essential, consequence

On Creation and Re-creation:

  • Original creation was made by God the Father through the Word (John 1:3)
  • Therefore re-creation should correspondingly be made through the Word by the power of God the Father
  • This maintains correspondence between creation and re-creation (2 Corinthians 5:19: “God was in Christ reconciling the world”)

Against the Holy Spirit’s Incarnation:

  • The Holy Spirit is the gift of both Father and Son
  • Remission of sins comes through the Holy Spirit as the gift of God
  • Therefore it is more suitable that the Son become incarnate, as the one of whom the Holy Spirit is the gift
  • When Christ breathes upon the apostles and says “whose sins you forgive, they are forgiven,” he is bestowing the Holy Spirit as the gift of justification

Human Nature’s Assumability (Q.4, Art.1) #

The Question #

  • Was human nature particularly suited to be assumed, or could God assume any creature equally?

Objections Raised #

Against human nature’s primacy:

  1. God’s power is infinite, not limited to one nature
  2. Irrational creatures share some likeness (footprint) of God
  3. Angels have more perfect likeness (image) than humans, and they too are subject to sin
  4. The universe as a whole is more perfect than human nature as a part

Thomas’s Response #

What Makes Something Assumable:

  • A nature is “assumable” not by abstract divine power but by aptitude (congruentia) for personal union
  • This aptitude is not a natural passive potency (which would exceed the natural order)
  • Instead, it is a certain appropriateness to the union itself
  • This congruence depends on two factors in human nature:
    • Dignity/worthiness of the nature itself
    • Necessity for redemption

Dignity: Rational Capacity:

  • Human nature, insofar as it is rational and understanding, is apt to touch the Word through its own operation
  • Man is ordered by nature to know and love God
  • This means man already has a certain aptness for union with God through his operations
  • Creatures without understanding (irrational beings) cannot attain God in himself through knowing and loving
  • Therefore they lack the congruence of dignity

Necessity: Subject to Redemption:

  • Man contracted original sin and requires preparation/remedy
  • Angels do not require redemption (their sin, once chosen, cannot be remedied)
  • Therefore angels lack the congruence of necessity
  • Both factors together belong only to human nature:
    • Dignity (rational capacity to know and love God): uniquely human among material creatures
    • Necessity (subject to redeemable sin): uniquely human among rational creatures

Response to Objections #

On Divine Power:

  • A creature is called “incurable” not to subtract from divine power but to show the creature’s own condition
  • Just as a sick person is incurable through his own principles (not that God cannot heal), so a creature is “not assumable” by its own nature
  • The question is not about divine power but about the aptitude of the creature
  • Creatures receive their property from their own causes, not from the universal first cause

On Irrational Creatures:

  • The likeness of the “footprint” (mere external representation) is insufficient
  • True union to God as person requires capacity to attain God by operation (knowing and loving)
  • What falls short in lesser union cannot have suitability for greater union
  • As a body not aptly perfected by a sensing soul is even less aptly perfected by an understanding soul

On Angelic Nature:

  • Some argue: Angels cannot be assumed because they are perfect from creation and do not undergo generation/corruption
  • Assumption would require destruction of the angel’s pre-existing personality
  • This contradicts divine goodness (which does not corrupt created perfection) and nature’s incorruptibility
  • Alternative: God could create an angelic nature as he unites it to himself, with no pre-existing personality
  • However, the essential defect remains: Angels cannot be redeemed (their sin is irreversible)
  • Thus they lack necessity, which human nature possesses
  • (Additional consideration: Each angel has a distinct nature, so assuming one angelic nature would exclude others; but many humans share one nature)

Important Definitions #

Congruentia / Convenientia (appropriateness, fittingness): Not absolute necessity but a suitable harmony between two things; appropriate relation based on their natures and purposes

Assumable (assumptibilis): Apt or suited to be assumed; having congruence to personal union with a divine person

Aptitude (aptitudo): Suitableness or readiness for something; in this context, the creature’s own disposition toward being assumed

Word / Logos (Λόγος): The second person of the Trinity; means both ‘word’ and ‘reason’ in Greek

Exemplar (exemplar): The model or pattern according to which something is made; the eternal thought of God by which creatures are made

Appropriation: Attributing to one divine person what belongs to all three, based on similarity to that person’s characteristic property

Examples & Illustrations #

The Artist and His Work #

  • The carpenter first conceives the form of a house in his mind
  • He then creates the physical house according to this mental form
  • The mental form is the exemplar of the physical house
  • If the house collapses, the artist repairs it by applying the same form
  • Application: God’s eternal thought (the Word) is the exemplar of all creation; when creation needs repair through sin, it is fitting that the Word (by whom it was made) restore it

The Teacher and Student #

  • A student advances in wisdom by receiving the teacher’s word
  • The teacher is the source and exemplar of the student’s knowledge
  • Application: Man advances in wisdom by partaking of the Word of God; therefore it is fitting that the Word unite to human nature to perfect it

Creation vs. Irrational Nature #

  • A body perfected by a sensing soul is aptly suited for sensing
  • That same body is not aptly suited for understanding (which exceeds its principle)
  • A lesser union (external likeness) does not have suitability for a greater union (personal union as divine person)
  • Application: Irrational creatures, lacking the operation by which to attain God, cannot be suited for personal union with God

Notable Quotes #

“In the mystery of the Incarnation is made known the wisdom and the power of God. The wisdom because he found a solution of a most difficult and most suitable [solution].” — John of Damascus (cited by Aquinas)

“God thought of man, had man in his mind, and then he created man, and man thought of God, and he had God in his mind. So he was reflecting the divinity just by thinking about the divinity.” — A Persian Father (cited by Berquist)

“There is nothing which cannot be abused by human malice, when even the goodness of God himself is abused.” — Aquinas (response to objection about Arian confusion)

Questions Addressed #

Why the Son Rather Than Father or Holy Spirit? #

  • Answer: While all three possess equal divine power and could have assumed human nature, the Son’s incarnation is most fitting because:
    1. The Word (Son) is the exemplar of all creation, making his personal union to creation especially congruous
    2. The Word has special affinity to human nature (both called Logos/reason)
    3. Man’s perfection comes through participation in the Word of wisdom
    4. Men become adopted sons through the natural Son
    5. Man’s sin of disordered knowledge is remedied by the incarnation of true Wisdom

Could the Arian heresy have arisen from any person’s incarnation? #

  • Yes. Error through human malice is always possible; the goodness of God itself can be abused. Nothing about assuming the Father would prevent confusion—if anything, it could suggest the Son is insufficient for redemption.

Why is human nature more assumable than other natures? #

  • Answer: Human nature alone possesses both requisite factors:
    1. Dignity: Rational capacity to attain and know God through its operations (which irrational creatures lack)
    2. Necessity: Subject to redeemable sin (which angels, fixed in their choice, lack)
  • Irrational creatures fail on dignity; angels fail on necessity
  • Only human nature satisfies both conditions