“As man is soul and body, Christ is God and Man”

In a few sermons for the feast of the Nativity, St. Augustine highlights the fact that God willed that Mary would remain a virgin through and after childbirth:

“Let us rejoice, my brethren, let the nations exult and be glad because, not the visible sun, but the invisible Creator of the sun has consecrated this day on which the Virgin, a true but inviolate Mother, gave birth to Him who became visible for our sake and by whom she herself was created. A virgin conceives, yet remains a virgin; a virgin is heavy with child; a virgin brings forth her child, yet she is always a virgin. 

Why are you amazed at this, O man? It was fitting for God to be born thus when He deigned to become man. Such did He make her, who was born from her; He existed before she was created; and, because He was omnipotent, He was able to become man while remaining what He was. He created His own Mother when He was with the Father; and when He was born of that Mother He remained in His Father. How would He who granted to His Mother the privilege of remaining a virgin when she brought forth her child cease to be God when He became Man? 

Furthermore, the fact that the Word became flesh does not imply that the Word withdrew and was destroyed on being clothed with flesh, but rather that flesh, to avoid destruction, drew near to the Word, so that, as man is soul and body, Christ might be God and Man. (Sermon 186)

"(The angel answered Mary:) You will remain a virgin; only believe the truth, preserve your virginity, even receive what will complete it. Your faith being honest, your virginity will remain unblemished. " (Sermon 291)

Saint Augustine (d. 430)

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