Being born of a virgin was common for heroes and god-men of the ancient world. Jesus’ virgin birth, aside from having to fit a common pattern, seems to have been based upon Matthew’s misreading of Isaiah 7:14 (Luke doesn’t even mention it). The Greek Septuagint which Matthew used translates it as “a virgin shall conceive and bear a son,” but the Hebrew word “almah” means “young woman of marriageable age,” not a virgin.
Nativity vs Gospels: Are the Gospels Reliable About Jesus’ Birth? (via revolutionaryatheist)