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

Subscribe in Podcast App | Download Transcript

Lecture Notes

Main Topics #

Why St. John Emphasizes Christ’s Flesh #

Thomas provides three reasons why the Gospels (especially John’s) emphasize that the Word became flesh:

1. Visibility and sensibility: The incarnate Word became visible and perceptible to the senses, unlike if He had assumed only a soul without a body
2. Arousal of love and hope: Emphasizing Christ’s abasement to the flesh increases our love for His humility and arouses hope in our own glorification (a fortiori argument: if God assumed flesh, the lowest part, surely He will glorify us)
3. Necessity for understanding: We are naturally led to the invisible through the sensible (per sensibilia ad intelligibilia), as demonstrated in the sacraments and miracles as “motives of credibility”

The Soul as a Necessary Assumption #

Thomas refutes the Apollinarian heresy (which denied Christ had a human soul, claiming the Word replaced the intellect):

• Gospel evidence: The Gospels narrate that Christ wondered (admiratio), which requires a human soul capable of wonder
• Redemption requirement: The soul of man is not capable of sin or grace except through the mind; therefore, Christ must have assumed the human rational soul so that the whole person could be redeemed
• True human nature: The soul is the form of the body (anima forma corporis). Without a soul, there would be no living human nature—only bestial flesh in human shape, which is absurd
• Damascene’s principle: “What is not assumed is incurable”—all parts of human nature must be assumed for complete redemption

The Human Mind/Intellect as Necessary #

Three objections attempted to deny that Christ possessed a human mind:

1. The image objection: Where the thing itself is present, its image is not needed
2. The greater light objection: The divine Word, as the greater light, should obfuscate the lesser light of the human intellect
3. The incarnation objection: “Incarnation” means assumption of flesh; the intellect is not flesh and should therefore not be assumed

Thomas’s responses:

• On the image: The divine Word’s presence perfects the image of God in the human mind (like a seal perfecting wax), rather than eliminating it. Union with the Word renews and restores the divine image
• On greater light: The sun’s light does not eliminate the light of stars in bodies illuminated by the sun; it perfects them. Similarly, the divine Word perfects the human intellect rather than obscuring it
• On incarnation and causality: Although the intellect is not the act of a body, the human soul (which is the form of the body) must possess intellectual power for the body to be truly human

The Order of Assumption: Temporal vs. Natural #

Thomas carefully distinguishes between two senses of “order”:

Temporal order: All parts of human nature (body, soul, intellect) were assumed simultaneously in the Incarnation. There is no temporal priority of soul before body or intellect before soul.

Natural order: There are two ways to observe natural order—

• By dignity: The soul is a middle between God and flesh because the soul is more like God than flesh; the intellect (spiritus) is a middle between God and soul
• By causality: The soul enables the flesh to be human; the intellect enables the soul to have its proper human operation

The divine Word’s union with human nature follows an order toward its end (God as final cause), in which higher creatures mediate lower ones (as Dionysius teaches in the Celestial Hierarchy). Thus, the soul serves as a fitting middle through which the Word unites to flesh, and the intellect serves as a middle through which the Word unites to the soul.

Response to the Objection about Soul Separation #

A subtle objection: If the soul is the means by which the Word unites to flesh, would not the soul’s separation at death also separate the Word from the flesh?

Thomas responds using three illustrations:

1. Friendship: One person may introduce two friends; when the intermediary leaves, the friendship remains
2. Marriage: A matchmaker arranges a marriage; when the matchmaker departs, the marital bond persists
3. Seal and image: The cause of something’s coming-to-be need not persist for the thing’s continued existence

Therefore, even though the soul is the fitting means of assumption, the Word’s union with the flesh persists after the soul’s separation (as exemplified in Christ’s death: the body in the tomb remained united to the Word while separated from the soul).

Key Arguments #

Against Denying a True Soul #

Objection: “The Word was made flesh” makes no mention of a soul; perhaps the Word simply replaced the soul.

Response:

• Scripture explicitly states Christ had a soul (Matthew 26:38; John 10:18)
• The Gospels narrate Christ’s wonder (admiratio), anger, and sorrow—operations requiring a true rational soul
• Without a soul, human nature would not be truly redeemed; the soul would remain incurable

Against Denying a Human Intellect #

Objection: The divine Word is light itself, enlightening every human mind. A human intellect would be superfluous or obfuscated.

Response:

• The human intellect is itself a light (illuminated from the first light). The divine Word perfects this light rather than eliminating it
• Christ’s actions in the Gospels (learning, teaching humility) demonstrate a true human intellect
• The human soul’s essence requires that it have intellectual power; the better the body, the better the soul it requires

On the Order of Assumption #

Objection: If the soul is a middle between God and flesh (by dignity), should it not have been assumed before the flesh in time?

Response:

• The soul is a middle in the order of nature (dignity and causality), not in the order of time
• The Incarnation occurred with all parts of human nature simultaneously
• The natural order reflects the order of causes leading back to God: intellect > soul > body in dignity, though all were assumed together temporally

Important Definitions #

Soul (anima): The substantial form of the body; the first act of a natural body. Source of all vital powers (vegetative, sensitive, rational). In humans, the rational soul is the form that makes the body human.

Spirit (spiritus): The higher, intellectual powers of the soul not dependent on bodily organs; specifically the intellect and will. The seat of the image of God (imago Dei) in human nature.

Flesh (caro): Used synecdochically to mean human nature as a whole (not merely bodily matter). Composed of the four elements and essential to Aristotelian human nature.

Hypostasis: An individual substance; a subsisting being. In the Incarnation, the Word’s hypostasis assumes human nature without that nature having its own hypostasis of subsistence.

Nature (natura): The essence of a thing; what makes it what it is. Human nature consists of body and soul united as matter and form.

Form and matter (forma et materia): In Aristotelian metaphysics, the principle by which a natural thing exists actually. The soul is the form; the body is the matter. Both are required for natural existence.

Examples & Illustrations #

The seal and wax: The divine Word’s presence perfects the human intellect as a seal perfects the image impressed in wax. The image is not eliminated by the seal but perfected by its impression.

The sun and stars: The sun’s light does not eliminate the light of stars but obscures it to our perception. The stars still possess their light and it is perfected in the sun’s presence. Similarly, the divine Word perfects the human intellect.

Friendship through an intermediary: One person introduces two others who become friends. When the introducer departs, the friendship remains. Similarly, the soul mediates the Word’s union to flesh, but the union persists after the soul’s separation at death.

Marriage and the matchmaker: A matchmaker arranges a marriage. Once the couple is united, the matchmaker’s departure does not dissolve the marital bond. The cause of union need not persist for the union to remain.

The First Vatican Council on motives of credibility: Berquist notes that miracles and the fulfillment of prophecies are universal motives of credibility (appropriate to all people) because they are sensible signs leading to invisible divine truths—contrasting with particular motives like Hilary recognizing the profundity of “I am who am” in the Old Testament.

Notable Quotes #

“What is not assumed is incurable.” — Damascene, cited by Thomas (emphasizing that all parts of human nature must be assumed for complete redemption)

“Hold most firmly and in no way doubt that Christ, the Son of God, had the flesh of our kind and the rational soul.” — Augustine, Epistle to Feliciana, cited in the lecture

“Learn from me who am meek and humble of heart.” — Christ, cited as proof that Christ possessed a human intellect and will capable of learning and teaching virtue

Questions Addressed #

Why did St. John emphasize that the Word became flesh? Because the Word became visible and sensible to our perception; we are naturally led to the invisible through the sensible. This emphasizes God’s humility, arouses our hope, and follows the pattern of how we know God through creation and sacraments.

Did Christ have a human soul? Yes. The Gospels narrate that Christ wondered and was saddened, acts requiring a human soul. Moreover, without a human soul, the soul would not be redeemed (for the soul is incurable without being assumed). The soul is the form of the body, making the body living and human.

Did Christ have a human intellect/mind? Yes. The Gospels narrate Christ’s wonder, anger, and sorrow—all requiring a human intellect. Without a human intellect, Christ would not have had a truly human nature but a bestial nature. The divine Word’s presence perfects rather than eliminates the human intellect.

Was the soul assumed before the flesh in time? No. All parts of human nature were assumed simultaneously in the Incarnation. However, in the natural order (by dignity and causality), the soul is a middle between God and flesh, and the intellect is a middle between God and soul.

Does the body’s separation from the soul at Christ’s death separate the Word from the flesh? No. Although the soul served as the fitting means (medium) of assumption, the Word’s union with the flesh persists even after separation from the soul, as exemplified by the body’s remaining in the tomb united to the Word.