Then said Mary unto the angel, How shall this be, seeing I know not a man?
All Commentaries on Luke 1:34 Go To Luke 1
Gregory The Dialogist
AD 604
By the term overshadowing, both natures of the Incarnate God are signified. For shadow is formed by light and matter. But the Lord by His Divine nature is light. Because then immaterial light was to be embodied in the Virgin's womb, it is well said to her, The power of the Highest shall overshadow you, that is, the human body in you shall receive an immaterial light of divinity. For this is said to Mary forthe heavenly refreshing of her soul.
To distinguish His holiness from ours, Jesus is stated in an especial manner to be born holy. Forwe although indeed made holy, are not born so, for we are constrained by the very condition of our corruptible nature to cry out with the Prophet, Behold, I was conceived in iniquity. ButHe alone is in truth holy, who was not conceived by the cementing of a fleshly union, nor as the heretics rave, one person in His human nature, another in His divine; not conceived and brought forth a mere man, and afterwards by his merits, obtained that He should be God, butthe Angel announcing and the Spirit coming, first the Word in the womb, afterwards within the womb the Word made flesh. Whence it follows, Shall be called the Son of God.