The human being who came to life in her womb took Mary’s flesh, but his existence derived totally from God. He is fully man, made of clay — to use the biblical symbol — but comes from on high, from Heaven. The fact that Mary conceived while remaining a virgin is thus essential to the knowledge of Jesus and to our faith, because it testifies that it was God’s initiative and, above all, it reveals who the conceived being was.

As the Gospel says: “the child to be born will be called holy, the Son of God” (Lk 1:35). In this sense, the virginity of Mary and the divinity of Jesus guarantee each other. This is what makes that single question so important that Mary, “greatly troubled”, asks the Angel: “How can this be, since I have no husband?” (Lk 1:34).

Mary was very wise in her simplicity. She did not doubt God’s power, but she wanted to better understand his will, in order to conform herself completely to this will. Mary was infinitely overcome by the Mystery, yet she occupied perfectly the place which, in its center, had been assigned to her. Her heart and her mind are fully humble and precisely because of her unique humility, God awaits this young woman’s “yes” in order to carry out his plan. He respects her dignity and her freedom. Mary’s “yes” entailed motherhood and virginity as a whole. She wanted everything in her to glorify God and he wanted the Son, born of her, to be totally a gift of grace.

Dear friends, Mary’s virginity is unique and unrepeatable; but its spiritual meaning concerns every Christian, who is essentially linked to faith. In fact, those who put deep trust in God’s love welcome Jesus and his divine life within them through the action of the Holy Spirit. This is the mystery of Christmas! I hope that you will all experience it with deep joy.

Pope Benedict XVI, Wednesday general audience, 18 December 2011