Nicene and Post-Nicene Fathers, Ser. II, Vol. III:
Life and Works of Rufinus with Jerome's Apology Against Rufinus.: Section 9. Who Was Born by (de) The Holy Ghost of the Virgin Mary

p. 547 9. “Who Was Born by (de) The Holy Ghost of the Virgin Mary.” This nativity among men is in the way of dispensation, 3277 whereas the former nativity is of the divine substance; the one results from his condescension, the other from his essential nature. He is born by the Holy Ghost of the Virgin. Here a chaste ear and a pure mind is required. For you must understand that now a temple hath been built within the secret recesses of a Virgin’s womb for Him of Whom erewhile you learnt that He was born ineffably of the Father. And just as in the sanctification of the Holy Ghost no thought of imperfection is to be admitted, so in the Virgin-birth no defilement is to be imagined. For this birth was a new birth given to this world, and rightly new. For He Who is the only Son in heaven is by consequence the only Son on earth, and was uniquely born, born as no other ever was or can be.

The words of the Prophets concerning Him, “A Virgin shall conceive and bring forth a Son,” 3278 are known to all, and are cited in the Gospels again and again. The Prophet Ezekiel too had predicted the miraculous manner of that birth, calling Mary figuratively “the Gate of the Lord,” the gate, namely, through which the Lord entered the world. For he saith, “The gate which looks towards the East shall be closed, and shall not be opened, and no one shall pass through it, because the Lord God of Israel shall pass through it, and it shall be closed.” 3279 What could be said with such evident reference to the inviolate preservation of the Virgin’s condition? That Gate of Virginity was closed; through it the Lord God of Israel entered; through it He came forth from the Virgin’s womb into this world; and the Virgin-state being preserved inviolate, the gate of the Virgin remained closed for ever. Therefore the Holy Ghost is spoken of as the Creator of the Lord’s flesh and of His temple.

Footnotes

Corresponding to the Greek word Economy—the “arrangement” or “plan” by which the Word became incarnate.

Isa. vii. 14

Ezek. xliv. 2, LXX.