Commentaria in Summam contra Gentiles, Liber IV

After St. Thomas has determined what the Catholic faith holds concerning the Incarnation¹, he wishes to exclude objections against the Incarnation itself². Concerning this, moreover, he does three things: first, he sets down the objections themselves; second, he introduces certain points for their solution, in the following chapter; third, he responds to them, in chapter XLIX.

As to the first, the Incarnation is attacked, first, because if God had assumed flesh, it would follow that he was changed into a body, or was a power in a body.

Second: because the hypostasis of the Son of God would have been substantially changed. For that which acquires a new nature is substantially changed.

Third: because the Son of God would not be everywhere after the Incarnation, since human nature is not everywhere. For no hypostasis of any nature is extended outside that nature.

Fourth: because, since of one thing there is only one quid est, it seems impossible for one hypostasis to subsist in two natures. For the nature of anything is its quid est.

Fifth: because it does not seem that the divine hypostasis can subsist in a human nature. Because in those things that are without matter, the quiddity and the supposit are the same. But the human nature cannot be the same as the divine hypostasis.