Homily by St. Jerome, Priest at Bethlehem

Book of Commentaries, on Matth. i.

Why was the Lord conceived of an espoused virgin rather than of a free? First, for the sake of the genealogy of Mary, which we have obtained by that of Joseph. Secondly, because she was thus saved from being stoned by the Jews as an adulteress. Thirdly, that Himself and His mother might have a guardian on their journey into Egypt. To these, Ignatius, the martyr of Antioch, has added a fourth reason namely, that the birth might take place unknown to the devil, who would naturally suppose that Mary had conceived by Joseph.