There are just two ‘nativity’ accounts, at the beginning of the Gospels called Matthew and Luke. Neither is referred to again in the New Testament, which nowhere else says anything about Jesus’ birth. The word “virgin” occurs only in Matthew, in a quote from Isaiah 7:14. Here’s a literal rendering of that verse from the Hebrew Bible : Look / the-young-woman / pregnant / and child-bearing / a son / and she will call / his name / ‘with-us / God’. Whence, then, the word “virgin”?
If the author in Isaiah wanted to make clear that he was writing about a “virgin”, he could’ve used the word בְּתוּלָה (bethulah) meaning precisely that. Instead, he used the word עַלְמָה (almah) which means a young woman of marriageable age who might, or might not, be a virgin. It seems unwise, then, to make any claim based on unclear, ambivalent ‘evidence’. Those who insist on the translation “virgin” are most likely to be those who regard the writer’s words as a “prophecy” of something that was to happen around 900 years in the future! That idea, I think, would have astonished the writer.
If we read the relevant chapter (without going into fine details) we discover that King Ahab of Israel was under threatening pressure from two other kings. The prophet Isaiah reassures him that it’s safe to hold out, and not give way. He points to a nearby young woman and says to Ahab. “Look, the young woman, who is pregnant, will give birth to a son” – and by the time he’s born, long before he’s old enough to know right from wrong – “the lands of those two kings who terrify you will be deserted.” That’s why the child can be called “Immanuel’ – God is with us. The “prophecy”, in other words, was about an imminent deliverance, not something 900 years later.
If not from the Hebrew Bible, where did the idea of ‘virgin birth’ come from? This is where we’re reminded of issues around translating from one language into another. By the 1st century, Hebrew was a minority language. People in Palestine spoke Aramaic and, in the Roman Empire, Greek was the lingua franca. To allow Jewish people to continue to read their scriptures, and to enable non-Jews to read them, they were translated, beginning from the 3rd century BCE, into a Greek version called the Septuagint. That’s the version that ‘Matthew’, based outside Palestine, and being a fluent Greek speaker, read and quoted from.
When the translators had arrived at Isaiah 7:14, for the word ‘almah’, they used παρθένος (parthenos) which means ‘virgin’. Lo and behold, that’s where Matthew got his idea of a ‘virgin birth’. There are no virgin births anywhere in the Hebrew Bible, or in Jewish tradition. This is a theme that belongs to the pagan world of Greek and Roman mythology – Romulus, the founder of Rome, was born of the virgin Rhea Silvia, fathered by the god Mars. Jesus was a man, born the same way as every other man.