On the Incarnation of the Lord, Against Nestorius

What then is that great mystery which is signified under the name of the man and his wife? Let us ask the Apostle himself, who elsewhere to teach the same thing uses words of the same force, saying: “And evidently great is the mystery of godliness, which was manifested in the flesh, justified in the Spirit, seen of angels, preached to the Gentiles, believed on in the world, received up in glory.” What then is that great mystery which was manifested in the flesh? Clearly it was God born of the flesh, God seen in bodily form: who was openly received up in glory just as He was openly manifested in the flesh. This then is the great mystery, of which he says: “For this cause shall a man leave his father and mother, and shall cleave to his wife; and they two shall be one flesh.” Who then were the two in one flesh? God and the soul, for in the one flesh of man which is joined to God are present God and the soul, as the Lord Himself says: “No man can take My life (anima) away from Me. But I lay it down of Myself. I have power to lay it down, and I have power to take it again.” You see then in this, three; viz., God, the flesh, and the soul. He is God who speaks: the flesh in which He speaks: the soul of which He speaks. Is He therefore that man of whom the prophet says: “A brother cannot redeem, nor shall a man redeem”? Who, as it was said, “ascended up where He was before,” and of whom we read: “No man hath ascended into heaven, but He who came down from heaven, even the Son of man who is in heaven.” For this cause, I say, He has left his father and mother, i.e., God from whom He was begotten and that “Jerusalem which is the mother of us all,” and has cleaved to human flesh, as to his wife. And therefore he expressly says in the case of the father “a man shall leave his father,” but in the case of the mother he does not say “his,” but simply says “mother:” because she was not so much his mother, as the mother of all believers, i.e., of all of us. And He was joined to his wife, for just as man and wife make but one body, so the glory of Divinity and the flesh of man are united and the two, viz., God and the soul, become one flesh. For just as that flesh had God as an indweller in it, so also had it the soul within it dwelling with God. This then is that great mystery, to search out which our admiration for the Apostle summons us, and God’s own exhortation bids us: and it is one not foreign to Christ and His Church, as he says, “But I am speaking of Christ and the Church.” Because the flesh of the Church is the flesh of Christ, and in the flesh of Christ there is present God and the soul: and so the same person is present in Christ as in the Church, because the mystery which we believe in the flesh of Christ, is contained also by faith in the Church.