- Discussion:
"Mary "remained a virgin in conceiving her Son, a virgin in giving birth to him, a virgin in carrying him, a virgin in nursing him at her breast, always a virgin" (St. Augustine, Serm. 186, 1: PL 38, 999): with her whole being she is "the handmaid of the Lord" (Lk 1:38)." (# 510)
The term "knew" was a modest way of describing sexual relations. That is how it is used in various places throughout the Old Testament (Genesis 4:1; 17; 25; Judges 11:39). To know carries with it connotations of people being intimate with each other. This idea of "knowing" is also expressed in the context of the covenant relationship between God and Israel (Amos 3:2; Hosea 2:14-23). Therefore, "knowing her not" in Matthew 1:25 means "keeping her a virgin" until marriage.
Children in Jewish culture were viewed as blessings from God (Psalm 127:3-5). The wife was likened to a vine and children to olive shoots (Psalm 128:3). The "barren womb" was said to "never be satisfied" (Proverbs 30:16). Children were viewed as a sign of divine favor (Genesis 21:6; 1 Samuel 1-2) . In fact, women who were unable to bear children felt humiliation and attributed their condition to some underlying sin or wrongdoing. For example, Rachel preferred death over childlessness (Genesis 30:1). This backdrop seriously weakens the Roman Catholic view of Matthew 1:25.
If we understand the clause "until" in Matthew 1:25 to indicate a change in the virginity status of Mary, then that reading would lend support to the virgin birth. It would further emphasize the fact that Jesus was not born as a result of sexual relations. Further, if Joseph had children from an earlier marriage, then Jesus would not have been recognized as the rightful heir to the Davidic throne. He would not have been Joseph's eldest son.
The Catholic dogma of Mary's perpetual virginity ignores the positive portrayal of childbearing by the Old Testament. It requires a highly unusual reading of Matthew 1:25, which centers around the marriage of Mary and Joseph. Matthew does not give us any indication whatsoever of Mary being a perpetual virgin. Why would a man abstain from sexual relations with his wife? Would it not have been unnatural for a Jewish woman to not have children? God created the sex act. He pronounced His creative work to be good upon finishing it (Genesis 1:31). Sex within the confines of marriage does not spiritually defile a person.