The Virgin Birth of Jesus Christ in the New Testament

Isaiah seven 14 prophecy only indicates that mary was to remain a virgin during her pregnancy and up to the messiah's birth. The greek word translated until does not exclude normal miratal conduct after jesus birth. If matthew wished to convey mary's virginity was perpetual, there would be no need to add, until she gave birth to a son. She would have simply ended with he kept her a virgin, or added throughout her marriage. As a believing jew and christian, mary would not have disobeyed god who commanded married couples to be fruitful and multiply. This is also the view of saint john chrysostom, as late as the fifth century