In both Eastern and Western art of the Annunciation, we often find that the trajectory of the descent of the Holy Spirit is not to the womb of the Virgin Mary, but to her ear. In complete deference to her virginity, the conception had nothing to do whatever with her female sexual organs, which remained forever intact. She did not conceive through her womb, but through her ear (conceptio per aurem). This teaching was inspired by the insights of many Church Fathers.
Several factors are operative here. Indisputably, writers and artists are striving to celebrate the total purity of Mary and the absence of any stain on her virginity. But they are also influenced by a Marian reading of a psalm: "Hear, O daughter, and consider, and incline your ear; forget your people and your father's house; and the King shall desire your beauty" (Ps. 45:10). Applied to Mary, "incline your ear" becomes a statement about the mode of conception as well as about her obedience to God. Mary is portrayed as the virgin whom the King of Kings desires to bear His son, Jesus. She does not become God's concubine, because by "inclining her ear," she remains a virgin even as she receives the royal Son.
The teaching of Mary's conception of Jesus through her ear is quite early, and apparently it was a rather commonplace belief among the Syriac writers of the Church. The chief statement to its effect is from St. Ephraim the Syrian:
It is a source of great amazement, my beloved
that someone should enquire into the wonder
of how God came down
and made his dwelling a womb,
and how that Being
put on the body of a man,
spending nine months in a womb,
not shrinking from such a home;
and how a womb of flesh was able
to carry flaming fire,
and how a flame dwelt
in a moist womb which did not get burnt up.
Just as the bush on Horeb bore
God in the flame,
so did Mary bear Christ in her virginity.
he entered the womb through her ear;
in all purity the God-Man came forth from the womb into creation.
Jacob of Serug also writes:
See how Eve's ear inclines and hearkens to the voice of the deceiver when he hisses deceit to her. But come and see the Watcher [Gabriel] instilling salvation into Mary's ear and removing the insinuation of the serpent from her and consoling her. [...] Instead of this virgin [Eve] another was chosen: truth was spoken to her in her ear from the Most High. By the door which death entered [i.e. the ear], by it entered life and loosened the great bond which the evil one had bound there.
And in the early seventh century, Venantius Fortunatus wrote:
Let ages henceforth marvel
that an angel brought the seed,
that in ear (hearing) the virgin conceived
and in heart believing she delivered.
Literary evidence of this motif was quite common in the early Church; art illustrations emerged in Renaissance Italy, in particular. But it was embedded in the popular literature of the Mediterranean world, Greek and Latin, in writing and art.
Conception through Mary's ear not only safeguards the physical nature of her virginity, but models a profound spiritual Christian truth. "Faith comes through hearing" (Rom 10:17). Mary is often portrayed as not seeing the angel, but only hearing his voice. Hearing in faith a word from God, she believes. Indeed Elizabeth praised Mary precisely for this: "Blessed is she who believed that there would be a fulfillment of what was spoken to her from the Lord" (Luke 1:45). Not only is Mary's physical virginity maintained by her conception through her ear, but her holiness as well. For she becomes not only the Virgin Mother of God, but the model disciple of the Word.