Thomas Aquinas - Summa Theologica, Part III (Tertia Pars)

Obj. 3: Further, the assumption of human nature by the Word of God is called His Incarnation. But the intellect or human mind is nothing carnal, either in its substance or in its act, for it is not the act of a body, as is proved De Anima iii, 6. Hence it would seem that the Son of God did not assume a human mind.

On the contrary, Augustine [*Fulgentius] says (De Fide ad Petrum xiv): "Firmly hold and nowise doubt that Christ the Son of God has true flesh and a rational soul of the same kind as ours, since of His flesh He says (Luke 24:39): 'Handle, and see; for a spirit hath not flesh and bones, as you see Me to have.' And He proves that He has a soul, saying (John 17): 'I lay down My soul [Douay: 'life'] that I may take it again.' And He proves that He has an intellect, saying (Matt. 11:29): 'Learn of Me, because I am meek and humble of heart.' And God says of Him by the prophet (Isa. 52:13): 'Behold my servant shall understand.'"

I answer that, As Augustine says (De Haeres. 49, 50), "the Apollinarists thought differently from the Catholic Church concerning the soul of Christ, saying with the Arians, that Christ took flesh alone, without a soul; and on being overcome on this point by the Gospel witness, they went on to say that the mind was wanting to Christ's soul, but that the Word supplied its place." But this position is refuted by the same arguments as the preceding. First, because it runs counter to the Gospel story, which relates how He marveled (as is plain from Matt. 8:10). Now marveling cannot be without reason, since it implies the collation of effect and cause, i.e. inasmuch as when we see an effect and are ignorant of its cause, we seek to know it, as is said Metaph. i, 2. Secondly, it is inconsistent with the purpose of the Incarnation, which is the justification of man from sin. For the human soul is not capable of sin nor of justifying grace except through the mind. Hence it was especially necessary for the mind to be assumed. Hence Damascene says (De Fide Orth. iii, 6) that "the Word of God assumed a body and an intellectual and rational soul," and adds afterwards: "The whole was united to the whole, that He might bestow salvation on me wholly; for what was not assumed is not curable." Thirdly, it is against the truth of the Incarnation. For since the body is proportioned to the soul as matter to its proper form, it is not truly human flesh if it is not perfected by human, i.e. a rational soul. And hence if Christ had had a soul without a mind, He would not have had true human flesh, but irrational flesh, since our soul differs from an animal soul by the mind alone. Hence Augustine says (Qq. lxxxiii, qu. 80) that from this error it would have followed that the Son of God "took an animal with the form of a human body," which, again, is against the Divine truth, which cannot suffer any fictitious untruth.

Reply Obj. 1: Where a thing is by its presence, its image is not required to supply the place of the thing, as where the emperor is the soldiers do not pay homage to his image. Yet the image of a thing is required together with its presence, that it may be perfected by the presence of the thing, just as the image in the wax is perfected by the impression of the seal, and as the image of man is reflected in the mirror by his presence. Hence in order to perfect the human mind it was necessary that the Word should unite it to Himself.

Reply Obj. 2: The greater light dims the lesser light of another luminous body; but it does not dim, rather it perfects the light of the body illuminated—at the presence of the sun the light of the stars is put out, but the light of the air is perfected. Now the intellect or mind of man is, as it were, a light lit up by the light of the Divine Word; and hence by the presence of the Word the mind of man is perfected rather than overshadowed.

Reply Obj. 3: Although the intellective power is not the act of a body, nevertheless the essence of the human soul, which is the form of the body, requires that it should be more noble, in order that it may have the power of understanding; and hence it is necessary that a better disposed body should correspond to it.

We must now consider the order of the foregoing assumption, and under this head there are six points of inquiry:

(1) Whether the Son of God assumed flesh through the medium of the soul?

(2) Whether He assumed the soul through the medium of the spirit or mind?

(3) Whether the soul was assumed previous to the flesh?

(4) Whether the flesh of Christ was assumed by the Word previous to being united to the soul?

(5) Whether the whole human nature was assumed through the medium of the parts?

(6) Whether it was assumed through the medium of grace? _______________________

FIRST ARTICLE [III, Q. 6, Art. 1]

Whether the Son of God Assumed Flesh Through the Medium of the Soul?

Objection 1: It would seem that the Son of God did not assume flesh through the medium of the soul. For the mode in which the Son of God is united to human nature and its parts, is more perfect than the mode whereby He is in all creatures. But He is in all creatures immediately by essence, power and presence. Much more, therefore, is the Son of God united to flesh without the medium of the soul.

Obj. 2: Further, the soul and flesh are united to the Word of God in unity of hypostasis or person. But the body pertains immediately to the human hypostasis or person, even as the soul. Indeed, the human body, since it is matter, would rather seem to be nearer the hypostasis than the soul, which is a form, since the principle of individuation, which is implied in the word "hypostasis," would seem to be matter. Hence the Son of God did not assume flesh through the medium of the soul.

Obj. 3: Further, take away the medium and you separate what were joined by the medium; for example, if the superficies be removed color would leave the body, since it adheres to the body through the medium of the superficies. But though the soul was separated from the body by death, yet there still remained the union of the Word to the flesh, as will be shown (Q. 50, AA. 2, 3). Hence the Word was not joined to flesh through the medium of the soul.

On the contrary, Augustine says (Ep. ad Volusianum cxxxvi): "The greatness of the Divine power fitted to itself a rational soul, and through it a human body, so as to raise the whole man to something higher."

I answer that, A medium is in reference to a beginning and an end. Hence as beginning and end imply order, so also does a medium. Now there is a twofold order: one, of time; the other, of nature. But in the mystery of the Incarnation nothing is said to be a medium in the order of time, for the Word of God united the whole human nature to Himself at the same time, as will appear (Q. 30, A. 3). An order of nature between things may be taken in two ways: first, as regards rank of dignity, as we say the angels are midway between man and God; secondly, as regards the idea of causality, as we say a cause is midway between the first cause and the last effect. And this second order follows the first to some extent; for as Dionysius says (Coel. Hier. xiii), God acts upon the more remote substances through the less remote. Hence if we consider the rank of dignity, the soul is found to be midway between God and flesh; and in this way it may be said that the Son of God united flesh to Himself, through the medium of the soul. But even as regards the second order of causality the soul is to some extent the cause of flesh being united to the Son of God. For the flesh would not have been assumable, except by its relation to the rational soul, through which it becomes human flesh. For it was said above (Q. 4, A. 1) that human nature was assumable before all others.