Mary: Despite her prominence in some Christian traditions, the gospels say relatively little about Jesus' mother. Luke 1:26 says Mary was a young girl or virgin (scholars debate the meaning of "parthenos," the Greek word used) when she conceived Jesus. However, both Luke and the first chapter of Matthew relate that Mary conceived Jesus "by the Holy Spirit." This is the basis for the traditional belief, shared by virtually all Christian denominations, in the virgin birth.
The common Protestant view is that after Jesus' birth, Mary and Joseph had natural children, who would have been Jesus' younger siblings. In Matthew 1:25, Jesus is called Mary's "firstborn son," an expression which many contend was used only if other children were born after the first one; otherwise, "only son" would have been used. Several New Testament passages refer to Jesus' siblings. In Matthew 13:55-56, villagers are skeptical of Jesus' powers, saying: "Is not this the carpenter's son? ...Are not his brothers James and Joseph Simon and Judas? Are not his sisters with us?" The first-century Jewish historian Josephus also refers to James, the brother of Jesus.
However, the Roman Catholic and Eastern Orthodox Churches teach that Mary remained a virgin all her life, even after the birth of Jesus. Catholics in particular have carefully scrutinized scriptural accounts that might imply Mary gave birth to additional children. The discovery, which adds strong evidence that Jesus had a brother, could spur debate among Catholic scholars. Historically, some Catholic scripture experts have contended that the Greek word "adelphos," used in the New Testament passages which describe Jesus' brothers, can mean a cousin or other relative, not necessarily a blood brother--and therefore, mentions of James did not contradict the belief that Mary remained a virgin.
Others, such as John Dominic Crossan, one of the leading scholars of the liberal Jesus Seminar, read the scripture differently. "In Mark's gospel, Jesus has brothers, four of them in fact. And two sisters," Crossan says. "And his father is Joseph and his mother is Mary....And the normal meaning for brother--well, you mean brother."
The Aramaic inscription on the ossuary of James uses the word "akhui" for brother. According to Protestant scholar Ben Witherington III, both the Aramaic word "akhui" and the Greek word "adelphos" usually refer to a blood brother. Both languages have other words for male cousins.
The Catholic belief in Mary's perpetual virginity is closely tied to one of the few ex cathedra--infallible--teachings of the Church, that of Mary's bodily assumption into heaven. In Munificentissimus Deus, Pope Pius XII declared that "the Blessed Virgin Mary's bodily Assumption into heaven--which surely no faculty of the human mind could know by its own natural powers, as far as the heavenly glorification of the virginal body of the loving Mother of God is concerned--is a truth that has been revealed by God and consequently something that must be firmly and faithfully believed by all children of the Church."
James: In addition to gospel references, the "brother of the Lord" is mentioned in several New Testament books. 1 Corinthians says that the risen Jesus appeared to James, and several sections of Acts detail James' leadership of Jerusalem's early Christians. While it's difficult to piece together what James' attitude toward his brother might have been before Jesus' crucifixion, it seems clear that James became a Christian afterward.
Josephus' account of James is one of the best extra-biblical proofs we have that Jesus had a brother. This text, which scholars consider generally reliable, describes "James, the brother of Jesus who was called the Christ," according to Biblical Archaeology Review. Josephus' account says that James was condemned to death in 62 C.E.--about 30 years after the death of Jesus, during the rule of the Roman governor Festus. "He was able to live in relationship both with Christian Jews and non-Christian Jews, and in fact when he was executed by the high priest it eventually caused the high priest to be dismissed," says Crossan. "In other words, he had pretty powerful friends, who probably weren't Christian."