Paul wrote more of the New Testament books than anyone else. But he started out as a bitter opponent and persecutor of the church. At that time his name was Saul.
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Saul became the top persecutor of the church, with the mission to destroy it. On his way to Damascus to arrest any and all Jews who had believed in Christ, God intervened:
As he was approaching Damascus on this mission, a light from heaven suddenly shone down around him. He fell to the ground and heard a voice saying to him, “Saul! Saul! Why are you persecuting me?”
“Who are you, lord?” Saul asked.
And the voice replied, “I am Jesus, the one you are persecuting! Now get up and go into the city, and you will be told what you must do” (Acts 9:3-6).
The men with Saul heard Jesus but could not see Him. For three days he was blinded until God led one of the believers to pray for him to see.
Immediately Saul changed his whole life direction (Acts 9:20):
Saul stayed with the believers in Damascus for a few days. And immediately he began preaching about Jesus in the synagogues, saying, “He is indeed the Son of God!”
Soon they had to sneak him out of town because now the Jews wanted to kill him.
In time he became the greatest missionary the church has ever had, and the apostle to the Gentiles, planting churches all over what is modern Turkey, Greece and Macedonia.
On his first mission trip he changed his name to Paul (Acts 13:9). The book of Acts records his ministry. At one point he stood before Caesar himself to defened himself and to share the good news of Christ (Acts 27:24). He was martyred in Rome around AD 64-67.
Of himself as a prisoner he said, "For me to live is Christ, to die is gain" (Philippians 1:21).
His letters to churchs are:
Romans; 1 & 2 Corinthians; Galatians; Ephesians; Philippians; Colossians; 1 & 2 Thessalonians; 1 & 2 Timothy; Titus; and Philemon.