48 But that blessed and true birth of the flesh conceived within the Virgin the Apostle has named both a creating and a making, for then there was born both the nature and form of our created being. And without doubt in his view this name belongs to Christ's true birth as a man, since he says, But when the fullness of the time came, God sent His Son, made of a woman, made under the law, in order that He might redeem those who are under the law, that we might obtain the adoption of sons. And so He is God's own Son, Who is made in human form and of human origin; nor is He only made but also created, as it is said: Even as the truth is in Jesus, that you put away according to your former manner of life, that old man, which becomes corrupt according to the lusts of deceit.
However, be ye renewed in the spirit of your mind, and put ye on that new man, which is created according to God. So the new man is to be put on Who has been created according to God. For He Who was Son of God was born also Son Man. This was not the birth of the divinity, but the creating of the flesh; the new Man taking the title of the race, and being created according to God Who was born before the ages. And how the new man was created according to God, he explains in what follows, adding, in righteousness, and in holiness, and in truth. For there was no guile in Him; and He has been made unto us righteousness and sanctification, and is Himself the Truth. This, then, is the Christ, created a new man according to God, Whom we put on.
Source: On the Trinity (New Advent)