On the contrary, Augustine [*Fulgentius] says (De Fide ad Petrum ii) that "God assumed the nature, not the person, of man."
I answer that, A thing is said to be assumed inasmuch as it is taken into another. Hence, what is assumed must be presupposed to the assumption, as what is moved locally is presupposed to the motion. Now a person in human nature is not presupposed to assumption; rather, it is the term of the assumption, as was said (Q. 3, AA. 1, 2). For if it were presupposed, it must either have been corrupted—in which case it was useless; or it remains after the union—and thus there would be two persons, one assuming and the other assumed, which is false, as was shown above (Q. 2, A. 6). Hence it follows that the Son of God nowise assumed a human person.
Reply Obj. 1: The Son of God assumed human nature in atomo, i.e. in an individual, which is no other than the uncreated suppositum, the Person of the Son of God. Hence it does not follow that a person was assumed.
Reply Obj. 2: Its proper personality is not wanting to the nature assumed through the loss of anything pertaining to the perfection of the human nature but through the addition of something which is above human nature, viz. the union with a Divine Person.
Reply Obj. 3: Absorption does not here imply the destruction of anything pre-existing, but the hindering what might otherwise have been. For if the human nature had not been assumed by a Divine Person, the human nature would have had its own personality; and in this way is it said, although improperly, that the Person "absorbed the person," inasmuch as the Divine Person by His union hindered the human nature from having its personality. _______________________
THIRD ARTICLE [III, Q. 4, Art. 3]
Whether the Divine Person Assumed a Man?
Objection 1: It would seem that the Divine Person assumed a man. For it is written (Ps. 64:5): "Blessed is he whom Thou hast chosen and taken to Thee," which a gloss expounds of Christ; and Augustine says (De Agone Christ. xi): "The Son of God assumed a man, and in him bore things human."
Obj. 2: Further, the word "man" signifies a human nature. But the Son of God assumed a human nature. Therefore He assumed a man.
Obj. 3: Further, the Son of God is a man. But He is not one of the men He did not assume, for with equal reason He would be Peter or any other man. Therefore He is the man whom He assumed.