James the Just, or a variation of James, brother of the Lord, was a brother of Jesus, according to the New Testament. He was the first leader of the Jerusalem Church of the Apostolic Age. Traditionally, it is believed he was martyred in AD 62 or 69 by being stoned to death by the Pharisees on order of High Priest Ananus ben Ananus. James, Joses, Simon, and Judas are mentioned as the brothers or siblings of Jesus as well as two or more unnamed sisters.

The brothers of Jesus or the adelphoi are named in the New Testament as James, Joses, Simon, Jude, and unnamed sisters are mentioned in Mark and Matthew. They may have been: (1) the sons of Mary, the mother of Jesus, and Joseph, (2) sons of Mary the wife of Cleophas and sister of Mary, the mother of Jesus; or (3) sons of Joseph by a former marriage. While option 1 is described as the "most natural inference" from the New Testament, those who uphold the perpetual virginity of Mary reject the idea of biological brethren and maintain that the brothers and sisters were either cousins of Jesus or children of Joseph from a previous marriage. The Lutheran Churches have accepted both option 2 and option 3 as being valid explanations for the doctrine of the perpetual virginity of Mary.