Simon is said to have been the brother (or half-brother) of Jesus, the son of St. Mary and Clopas. He is only mentioned in passing in the Bible (Matthew 13:55, Mark 6:3), but he is sometimes identified with Simeon of Jerusalem and Simon the Zealot.
Simon's other siblings included James the Just and Joses. Simon was allegedly seen as the "third in line" to lead the church, after his supposed brothers Jesus and James. Early church writers depicted Simon as Jesus' cousin, but James Tabor concludes that Simon was probably Jesus’ half-brother. After the death of St. Joseph, Mary, the mother of Jesus, apparently married Clophas and had other children, including Simon.