Reply Obj. 1: Although the intellect is not distinct from the soul in essence, it is distinct from the other parts of the soul as a power; and it is in this way that it has the nature of a medium.
Reply Obj. 2: Fitness for assumption is wanting to the angelic spirits, not from any lack of dignity, but because of the irremediableness of their fall, which cannot be said of the human spirit, as is clear from what has been said above (I, Q. 62, A. 8; First Part, Q. 64, A. 2).
Reply Obj. 3: The soul, between which and the Word of God the intellect is said to be a medium, does not stand for the essence of the soul, which is common to all the powers, but for the lower powers, which are common to every soul. _______________________
THIRD ARTICLE [III, Q. 6, Art. 3]
Whether the Soul Was Assumed Before the Flesh by the Son of God?
Objection 1: It would seem that the soul of Christ was assumed before the flesh by the Word. For the Son of God assumed flesh through the medium of the soul, as was said above (A. 1). Now the medium is reached before the end. Therefore the Son of God assumed the soul before the body.
Obj. 2: Further, the soul of Christ is nobler than the angels, according to Ps. 96:8: "Adore Him, all you His angels." But the angels were created in the beginning, as was said above (I, Q. 46, A. 3). Therefore the soul of Christ also (was created in the beginning). But it was not created before it was assumed, for Damascene says (De Fide Orth. iii, 2, 3, 9), that "neither the soul nor the body of Christ ever had any hypostasis save the hypostasis of the Word." Therefore it would seem that the soul was assumed before the flesh, which was conceived in the womb of the Virgin.
Obj. 3: Further, it is written (John 1:14): "We saw Him [Vulg.: 'His glory'] full of grace and truth," and it is added afterwards that "of His fulness we have all received" (John 1:16), i.e. all the faithful of all time, as Chrysostom expounds it (Hom. xiii in Joan.). Now this could not have been unless the soul of Christ had all fulness of grace and truth before all the saints, who were from the beginning of the world, for the cause is not subsequent to the effect. Hence since the fulness of grace and truth was in the soul of Christ from union with the Word, according to what is written in the same place: "We saw His glory, the glory as it were of the Only-begotten of the Father, full of grace and truth," it would seem in consequence that from the beginning of the world the soul of Christ was assumed by the Word of God.
On the contrary, Damascene says (De Fide Orth. iv, 6): "The intellect was not, as some untruthfully say, united to the true God, and henceforth called Christ, before the Incarnation which was of the Virgin."
I answer that, Origen (Peri Archon i, 7, 8; ii, 8) maintained that all souls, amongst which he placed Christ's soul, were created in the beginning. But this is not fitting, if we suppose that it was first of all created, but not at once joined to the Word, since it would follow that this soul once had its proper subsistence without the Word; and thus, since it was assumed by the Word, either the union did not take place in the subsistence, or the pre-existing subsistence of the soul was corrupted. So likewise it is not fitting to suppose that this soul was united to the Word from the beginning, and that it afterwards became incarnate in the womb of the Virgin; for thus His soul would not seem to be of the same nature as ours, which are created at the same time that they are infused into bodies. Hence Pope Leo says (Ep. ad Julian. xxxv) that "Christ's flesh was not of a different nature to ours, nor was a different soul infused into it in the beginning than into other men."