Mary was NOT a Perpetual Virgin

Mt 1:24-25 Then Joseph being raised from sleep did as the angel of the Lord had bidden him, and took unto him his wife: And knew her not till she had brought forth her firstborn son: and he called his name JESUS.

 
The Holy Spirit tells us here that Joseph knew her not (sexually) until after the birth of Jesus Christ. Study the Jewish wedding and you will see what constitutes a marriage - consummation.
 
Galatians 1:19 But other of the apostles saw I none, save James the Lordís brother.
 
Mt 13:55  Is not this the carpenterís son? is not his mother called Mary? and his brethren, James, and Joses, and Simon, and Judas?

Mr 6:3  Is not this the carpenter, the son of Mary, the brother of James, and Joses, and of Juda, and Simon? and are not his sisters here with us? And they were offended at him.
 
Mary was not - and is not - a perpetual virgin. She had a normal married life, lived under the law, a blessed marriage consummated under the law, followed Jewish tradition, obedient to God. All the internal evidence of the Bible shows she had no less than than four sons and at least two daughters making for a family of at least, AT LEAST seven children!