How did Paul take a small Jewish movement to the wider Roman world?

A man who never met Jesus in life did more than almost anyone to carry his message across the Roman world. Paul, born Saul of Tarsus, was a Christian apostle who founded several Christian communities in Asia Minor and Europe from the mid-40s to the mid-50s AD. He was not one of the Twelve Apostles and did not know Jesus during his lifetime, though he did know eyewitnesses such as Peter, John and Jesus's brother James from the mid 30s AD.

He began on the other side. According to Acts, Paul was a Pharisee who took part in persecuting the early disciples of Jesus, until, Acts says, on his way to arrest Christians in Damascus, he saw a bright light and heard Christ speak. He was also well placed for the task ahead. He came from Tarsus, in the Roman province of Cilicia, one of the larger centers of trade on the Mediterranean coast, and he used a second name, Paulus, for communicating with a Greco-Roman audience. His method was to put his message in a language and style relatable to each audience, and he drew on Stoic terms and metaphors to help Gentile converts understand it.

The movement's first big question was whether non-Jews had to be circumcised to join. At a meeting in Jerusalem around AD 49, Peter, James and John, whom Paul calls Pillars of the Church, accepted his mission to the Gentiles. The dispute did not end there: Paul recounts that he publicly confronted Peter at Antioch, the city where followers of Jesus were first called Christians, because Peter would not share a meal with Gentile Christians who did not strictly follow Jewish customs.

His letters spread his teaching further. Fourteen New Testament books have traditionally been attributed to him, though only seven are undisputed by scholars as authentic. He is believed to have died after the Great Fire of Rome in AD 64.