WELS affirms the literal, biological virgin birth of Jesus Christ—that Mary conceived and bore Jesus without a human father, and that the Holy Spirit was the agent of this supernatural conception. This doctrine is grounded in Scripture (Matthew 1:18-25; Luke 1:26-38) and is affirmed as a historical reality and a demonstration of divine power.

However, WELS explicitly teaches that Mary was not perpetually virginal. Scripture indicates that Mary and Joseph had other children after Jesus' birth (Matthew 13:55-56; Mark 6:3). Mary is honored as the virgin mother of Jesus and is accorded respect, but she is not venerated as divine, sinless (immaculate), or as a co-redemptrix. WELS rejects Roman Catholic and Eastern Orthodox doctrines concerning Mary's perpetual virginity, immaculate conception, bodily assumption, and intercessory role.

The virgin birth of Jesus is essential to Christian faith, affirming that Jesus is truly the God-man, that his birth was a miraculous divine act, and that he entered the world without inheriting the guilt of Adam's transgression. Mary herself, however, is a redeemed sinner who stands under grace like all other believers.