Little is recorded of him aside from his name.
The Bible calls him Simon the Zealot (in Luke 6:15 and Acts 1:13), perhaps a reference to his political affiliation. Simon , the eleventh apostle, was chosen by Simon Peter. He was an able man of good ancestry and lived with his family at Capernaum. He was twenty-eight years old when he became attached to the apostles. He was a fiery agitator and was also a man who spoke much without thinking. He had been a merchant in Capernaum before he turned his entire attention to the patriotic organization of the Zealots.
There are several versions of his travels:
- He was believed to have left Jerusalem and travelled first to Egypt and then through North Africa to Carthage. From there he went to Spain and then north to Britain, where he was crucified by the Romans in Caistor, Lincolnshire, and subsequently buried there on May 10, circa 61 AD.
- There is also a belief that he, along with the apostle Jude, were thought to have preached together in Syria and Mesopotamia travelling as far as Persia (modern Iran). They are also believed to have been martyred there (Simon being sawn in half and Jude being martyred with a halberd).
- The most widespread belief is that after evangelizing in Egypt, he joined Jude in Persia (Iran) and Armenia or Beirut, Lebanon, where both were martyred in 65 AD.
- Christian Ethiopians claim that he was crucified in Samaria, while Justus Lipsius writes that he was sawn in half at Suanir, Persia. However, Moses of Chorene writes that he was martyred at Weriosphora in Caucasian Iberia. Tradition also claims he died peacefully at Edessa.