Mary & the Saints
Mary's Perpetual Virginity
Mary remained a virgin before, during, and after the birth of Jesus, a teaching held by the whole ancient Church including the earliest Reformers.
Catholic teaching
Mary's total consecration to God as 'ever-virgin' reflects her unique vocation as the Mother of God and the fittingness of the Lord's exclusive dwelling in her womb. The 'brothers of the Lord' mentioned in the Gospels are understood, per ancient Semitic usage and consistent tradition, as close relatives rather than other children of Mary.
Biblical foundation
Mary's question 'How can this be, since I know not man?' suggests a vow or resolve of virginity even within marriage. From the cross, Jesus entrusts Mary to John rather than to any brother, which would be unusual if she had other sons to care for her.
Scripture references
Historical evidence
Belief in Mary's perpetual virginity was held universally in the early Church and affirmed even by the Protestant Reformers Martin Luther, John Calvin, and Ulrich Zwingli, showing it was not a late Catholic invention but the historic Christian consensus.
The Church Fathers
“You say that Mary did not remain a virgin; I claim that she remained a virgin even more after the birth.”