Barnabas (Byzantium!)

 was a Jewish priest — and, according to Amos, a prophet — who converted to Christianity in the 1st century, and was instrumental to the early attempts to spread the influence of the then-new religion. Towards this end, he travelled throughout the Mediterranean Roman Empire with Paul, Luke and Timothy. He was he the cousin of Mark of Jerusalem, another of the early Christian leaders. (PDA: Byzantium!)