Paul generally refers to Saint Paul, also called Paul of Tarsus or Saul of Tarsus. Paul is an important figure in the early church, according to tradition and the Acts of the Apostles he started off as Saul and persecuted the Christians but experienced a vision or Hallucination on the road to Damascus. After that he converted to Christianity and changed his name to Paul. Saint Paul became a Christian missionary and wrote many epistles though it is likely that Paul did not write all the epistles attributed to him.  Different texts epistles attributed to Paul contradict each other and some may have been for specific early churches rather than for the whole of Christendom.