Significance of the Apostle Paul
It has been said that if it were not for Paul and a few others such as Barnabas that Christianity would have remained a small unknown branch of Judaism. Paul was the leading missionary to the Gentiles.
Gentiles are the name given to people who are not Jewish. While many within the early church were determined that a Christian must first become a Jew, Paul insisted that this was not the case. Paul recognized that the message of Jesus was for all men. In a letter to the Galatians he thoroughly spelled out a case for the message of Jesus being a "New Covenant" with humanity.
Abraham accepted God of his free will, and God favored Abraham for this reason. This was the covenant that God made with Abraham and his descendants. The laws given to Moses were not set down for another couple hundred years. So Paul believed that they were not part of the original bargain, but were given later to Moses as an intermediate guide until Jesus came to set down the new "Law" and the New Covenant. He noted that Jesus died on the Cross not only for our sins, but to take on the burden of Mosaic Law. Thus, a Christian need not first become a Jew in order to follow Jesus. Paul said that like Abraham Christians are saved by their faith alone.
This insistence would have huge repercussions in the early 1500s when the reformation was sparked by Martin Luther in Germany. One of the differences between Luther and the Catholic church was Luther's belief, based on the writings of Paul, that men could not be saved by their good works but only on their belief in God. Of course, the debate over how important acting like a Christian is has raged ever since.
Paul, himself, seems to have been of the opinion that faith was all that was required. Nevertheless, a truly faithful person would act Christianly.
He succeeded in making Christianity a universal religion, not just in the spiritual sense but also in the physical sense. Spreading the Gospel far and wide across the Roman Empire was Paul's mission. His missionary journeys brought him to Asia Minor, Greece, Macedonia and eventually Rome. There is no question that his Roman citizenship and his intense training as a Pharisee helped him immensely in this mission. He was arrested several times because of his preaching and several times was saved because of his elevated status within the Empire.
Besides being a fiery orator, Paul was also a capable writer. His letters make up the bulk of the epistles in the Bible. Because his writings were so treasured, they are among the most studied today. The words of Paul carry weight far greater than those of James or Peter, some of whose letters also survive. Paul's thoughtfulness, gentleness and steadfastness infuse his letters and they also infuse the close adherents of his words today.
Paul was a charismatic individual. He was a sure leader of men. Seldom did he doubt himself. He saw his mission as not only bringing the "Good News" to the Gentiles, but also to organize the Church so that it would grow, even when he was not present to urge it on. Thus, he created an organization and trained leaders. This organization would one day become modern Christianity as it came to supersede the original authority of the Church in Jerusalem.
Today Christians see Christ somewhat through the prism of Paul's teaching. Paul's follower, Luke, would write one of the Gospels as well as the Book of Acts. Paul was vitally shaped by a dramatic meeting with Christ on the Road to Demascus and it was this drama, coupled with his fervor that would mold Christianity for the next two Millenia.
Ultimately, it was Paul who both physically and theologically made Christianity a "universal" church.