The Virgin Mary - Interpretive Differences within the Church
When Catholics refer to the Virgin Mary, they mean she remained a virgin throughout her life. When Protestants refer to Mary as a "virgin," they mean she was a virgin until the birth of Jesus. Let's take a look at the scripture...
The Virgin Mary - A Review of Scripture
Although Christians generally refer to the mother of Jesus as the "Virgin Mary," the Bible appears to teach that Mary and Joseph had additional children after the miraculous birth of Christ. There are about ten instances in the New Testament where "brethren of the Lord" are mentioned (Matthew 12:46; Matthew 13:55; Mark 3:31-34; Mark 6:3; Luke 8:19-20; John 2:12, 7:3, 5, 10; Acts 1:14; 1 Corinthians 9:5). For instance, in Matthew 13:55 and Mark 6:3, James, Joseph, Simon and Judas are called Jesus' "brothers" and seem to be included in the same family unit as Joseph, Mary and Jesus.
The Virgin Mary - Another Scriptural Thought
The Bible gives no clear instance where God commands a married couple to abstain from sex permanently. In fact, in 1 Corinthians 7:3-5, we are told that a man should enjoy his wife and a wife her husband, and that the couple should only abstain from sex by mutual consent and only for a time. But perhaps God commanded Joseph never to enjoy his wife. We don't know. The Bible doesn't specify. What we know for certain is that Joseph "had no union with her until she gave birth to a son" (Matthew 1:25). The "until" seems to imply that he did enjoy sexual union with Mary after Christ's birth. There is no indication that their abstinence was permanent.
The Virgin Mary - Does any of this Matter?
Our concern shouldn't be whether or not the "Virgin Mary" remained a virgin after the birth of Christ. That doesn't have any biblical bearing on our salvation, and therefore, is a peripheral issue. Certainly, Christian doctrine holds that Mary remained a virgin until at least after Christ was born. Thereafter, an argument could be made either way. However, if the perpetual virginity of Mary is used as part of the doctrine holding her to a level of worship, especially as Co-mediatrix with Christ, then we must question the motivation for that interpretation. The Bible teaches that we must trust in Christ - and Christ alone -- for salvation. Adding to or subtracting from what Jesus Christ did on the cross is unbiblical, and therefore, very misguided.