Was Mary a “perpetual virgin” as is taught by the Roman Catholic Church, or did she have normal conjugal relations with Joseph after the birth of Jesus Christ?
The Catechism of the Catholic Church, Par. 499 says “the liturgy of the Church celebrates Mary as the ‘Ever-virgin.’” Par. 500 explains: “Against this doctrine the objection is sometimes raised that the Bible mentions brothers and sisters of Jesus. The Church has always understood these passages as not referring to other children of the Virgin Mary. In fact James and Joseph, ‘brothers of Jesus,’ are the sons of another Mary, a disciple of Christ, whom St. Matthew significantly calls ‘the other Mary.’ They are close relations of Jesus, according to an Old Testament expression.”
In Matthew 13:55 we read that when Jesus came to Nazareth people asked, “Is not this the carpenter’s son? Is not his mother called Mary? And his brethren, James, and Joses, and Simon, and Judas? And his sisters, are they not all with us?” The context clearly indicates which “Mary” is being referenced—it is Mary, the mother of Jesus according to His human nature. The text also indicates that He had brothers and sisters.
Roman Catholic apologists will claim that in the original Aramaic, “brothers and sisters” could simply be a reference to male and female relatives. However, God didn’t give us an Aramaic New Testament. He gave us a Greek New Testament, and “brothers” and “sisters” means blood relatives, siblings, half-brothers and half-sisters. Matthew 12:46–47 explicitly connects them with Mary, indicating that they were not cousins, nor were they from Joseph’s previous marriage. These are the brothers and sisters of Jesus. The Bible does not call them his “kindred.”
Matthew 1:25 speaks about Mary and states that Joseph “knew her not till she had brought forth her firstborn son.” Mary was a virgin prior to the birth of Jesus, but not after. This verse states that Jesus was her “firstborn.” It does not suggest that Jesus was her “only born.”
In the ancient Jewish society in which Mary lived, there was no reason for her to take a vow of perpetual chastity. She was engaged to be married and there is no indication that “marriage” in her case was anything other than what it means in every other case. Celibacy was not highly esteemed in ancient Jewish society the way it was in the Middle Ages in Europe. Why would Mary be a perpetual virgin? To argue that Mary had taken some kind of vow of celibacy would go against everything in ancient Jewish life. Celibacy was not considered a higher state of spirituality. Hebrews 13:4 teaches that marriage is to be held in high esteem and the marriage bed undefiled. One cannot teach the perpetual virginity of Mary from the Bible. It is taught because of other considerations which are foreign to Scripture.