Simon (brother of Jesus)
In Matthew 13:55, people ask concerning Jesus, "Is not this the carpenter's son? is not his mother called Mary? and his brethren, James, and Joses, and Simon, and Judas?" while in Mark 6:3 they ask, "Is not this the carpenter, the son of Mary, the brother of James, and Joses, and of Juda, and Simon? and are not his sisters here with us?"
Consistent with its doctrine of the perpetual virginity of Mary, the Catholic Encyclopedia rejects the idea that Simon was a biological son of Mary, suggesting that the so-called Desposyni were either sons of Joseph from a previous marriage (in other words, step-brothers) or else were cousins of Jesus. The Catholic Encyclopedia suggests that Simon may be the same person as Simeon of Jerusalem or Simon the Zealot. Protestant interpreters usually take Simon to have been a half-brother of Jesus.
In The Jesus Dynasty, James Tabor suggests that Simon was the son of Mary and Clophas. Robert Eisenman further suggests he was Simon Cephas (Simon the Rock), known in Greek as Peter (from petros = rock), who led the Jewish Christian community after the death of James in 62 CE.