The announcement in Luke 1:26-38 is the most detailed:“Do not be afraid, Mary, for you have found favor with God. And behold, you will conceive in your womb and bear a son and you shall call his name Jesus.” And Mary said to the angel, “How can this be since I have no husband?” And the angel said to her, “The Holy Spirit will come upon you and the power of the Most High will overshadow you; therefore, the child to be born will be called holy, the Son of God for with God, nothing is impossible.” Mary said, “Behold, I am the handmaid of the Lord; let it be done to me according to your word.”
Roman Catholic History of the Annunciation of the Lord
Originally a feast of our Lord, but now celebrated as a Marian feast (in honor of Mary), the feast of the Annunciation dates back at least to the fifth century.
The Annunciation, as much as or even more so than Christmas, represents Christ’s incarnation. When Mary signaled to Gabriel her acceptance of God’s Will, Christ was conceived in her womb through the power of the Holy Spirit. While most of the fathers of the church say that Mary’s fiat was essential to God’s plan of salvation, God foresaw Mary’s acceptance of his Will from all eternity.
The narrative of the Annunciation testifies powerfully to the truth of the Catholic tradition that Mary was indeed a virgin when Christ was conceived, but also that she intended to remain one perpetually. Mary’s response to Gabriel, “How can this be since I have no husband?” in Luke 1:34 was universally interpreted by the fathers of the church as a statement of Mary’s resolution to remain a virgin forever.