Saint Simon is believed to have been a relative of Jesus, possibly a first cousin. He is mentioned in the Gospel of Matthew and is counted among the brethren of Christ referred to in the Acts of the Apostles, where he was present at the birth of the Church on the first Pentecost.
Tradition holds that he witnessed the martyrdom of Saint James the Lesser and was later chosen to succeed him as Bishop of Jerusalem. In the year 66, before Jerusalem fell to the Romans, Christians received a divine warning and fled to the nearby town of Pella, with Saint Simon guiding them to safety.
After the destruction of Jerusalem, Saint Simon led the faithful back to the city. Under his leadership the Christian community grew, many people were converted, and miracles were reported.
He was eventually arrested and tortured, and he suffered martyrdom because he was both Jewish and Christian. Saint Simon died by crucifixion.