IMO Mary was not a virgin when she gave birth to Jesus.

Matthew, did not meet Jesus until Jesus was about 30 years old. [Matthew 9:9]
Luke does not claim to be an eye witness but only a compiler who never had even met Jesus [Luke 1:1-3]
So both gospel writers who report the virgin birth were at least 30 years away from Jesus’ birth.
How could they know about Jesus’ birth?

My mother always tells me that I was born of a virgin.
Just like Jesus, there is no way to tell if a mother was a virgin when her child was born, nor is there any way to tell if a child was born of a virgin.

About the time that Mary became pregnant she went on a trip to visit her relative, Elizabeth, in the hill country. [Luke 1:39] So she was not being watched by her family or the people of her town. Any five minute interlude could have done the deed.

The relatives and people of Mary’s town could not be witnesses of Mary’s virginity. When it was noticed Mary was pregnant Joseph didn’t want to disgrace or embarrass Mary . [Matthew 1:18-19] So Joseph probably took “credit” for Mary’s pregnancy. To tell everyone that Mary was pregnant and still a virgin would have been ridiculous. Nobody would have believed him. LOL.

So the only possible witness could have been Mary, herself. Why should we believe her? Mary’s two or three witnesses are no where in sight.
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