Originally posted by RBHILL
Was Mary a virgin her whole life? I don't think it would be possible because Joseph took her as his wife. And the Bible claims Jesus had half brothers ans sisters. And when he was a yuong child he was left behind in Jerusalem by his parents so I just don't see joseph being with her and not getting some.
The perpetual virginity of Mary was a universal belief in Christendom until Protestant times, although even Luther and Calvin accepted the doctrine. Perhaps the only point contended in the early church was whether Mary's virginity was preserved
in partu (i.e. Jesus was born without any damage to Mary's hymen.) St Jerome in the fourth century deals exhaustively with this subject in his work
In Helvidium. He argues that the brothers and sisters were in fact cousins (because the original Aramaic expression did not distinguish brothers from cousins). He argues also that if Mary had other children, then there would have been no reason for Jesus during his crucifixion to give John as a son to Mary. He also traces the brothers explicitly named in Scripture to other mothers:
http://www.newadvent.org/fathers/3007.htm
St Jerome's arguments however were not alone. In the Eastern churches, Jesus' brothers and sisters were generally believed to have been step-siblings, Joseph's children from a previous marriage.