Saul, also known as Paul, was the great apostle to the Gentiles. Three elements of the world's life of that day, Greek culture, Roman citizenship, and Hebrew religion met in the apostle to the Gentiles. Saul was born of purest Jewish blood (Phil. 3:5). Saul was never ashamed to acknowledge himself as a Jew (Acts 21:39). Saul was the son of a Pharisee (Acts 23:6) and he was brought up in orthodox Judaism. At the proper age Saul was sent to Jerusalem and completed his studies under the famous Gamaliel (Acts 22:3; 26:4-5). Having been educated among the strictest of the Pharisees, we easily can see a reason for the persecutions he heaped upon Jesus' followers.
But God had a use for this persecutor. He was to be a chosen vessel of His ministrations to the Gentiles, and He was to convert him in a special and distinct way. We read about Saul bearing record of his calling in Acts. And when we were all fallen to the earth, I heard a voice speaking unto me, and saying in the Hebrew tongue, Saul, Saul, why persecutest thou me? it is hard for thee to kick against the pricks. And I said, Who art thou Lord? And he said, I am Jesus whom thou persecutest. But rise, and stand upon thy feet: for I have appeared unto thee for this purpose, to make thee a minister and a witness both of these things which thou hast seen, and of those things in the which I will appear unto thee; Delivering thee from the people, and from the Gentiles, unto whom now I send thee, To open their eyes, and to turn them from darkness to light, and from the power of Satan unto God, that they may receive forgiveness of sins, and inheritance among them which are sanctified by faith that is in me (Acts 26:14-18KJV)
The new convert proclaimed the Messiahship of Jesus in the Jewish synagogues in Damascus, truths that had seized his soul (Acts 9:20-22). Saul left from Damascus and went to Jerusalem where he met Barnabas (Acts 9:26-27). Together, Paul and Barnabas spread the ministry of Jesus Christ to the Gentiles. After fulfilling their ministry there Saul and Barnabas returned from Jerusalem. They went to Antioch and went into the synagogue on the sabbath day and sat down (Acts 13:14). After the reading of the law and prophets the rulers of the synagogue sent unto them, saying, Ye men and brethren, if ye have any word of exhortation for the people, say on (Acts 13:15). Paul stood up and preached beginning with 'the God of this people of Israel chose our fathers' and ending with 'Be it known unto you therefore, men and brethren, that through this man is preached unto you the forgiveness of sins: And by him all that believe are justified through the law of Moses' (Acts 13:38-39). Saul boldly preached Christ everywhere that he went.
Saul's first missionary journey took him to Asia Minor, where he first used the name of Paul. On the second missionary journey the faith was taken across the continental boundary into Europe. After the third missionary journey the Jews, who still hated him with consuming force, succeeded in getting him thrown in jail. His enemies almost killed him, but he was rescued by Roman soldiers, and for a time kept in chains.
Paul is one of the most remarkable characters in all history. He fearlessly and dynamically spread the ministry of Jesus Christ to the Gentiles. For further reading on the life and missionary work of Paul, the main biblical source is found in The Acts Of The Apostles. Paul was also a writer and wrote several books of the bible. He wrote Romans and Galatians: doctrines of sin and grace; 1 and 2 Corinthians: moral and practical questions; Colossians and Philippians: person of Christ; Ephesians: the church of Christ; 1 and 2 Timothy and Titus: church government and pastoral care; Philemon: slavery; and, Hebrews: the eternal priesthood and sacrifice of Christ.