Read: Acts 9:20-25
And immediately he proclaimed Jesus in the synagogues, saying, “He is the Son of God.” (Acts 9:20 ESV)
The story of Saul of Tarsus is incredible. He first came onto the scene of scripture as a persecutor of Christ's first generation of followers. But after a roadside experience with the resurrected Jesus—Saul was irrevocably ruined as a Pharisee.
No longer could he stomach the jealous hatred that drove his order to dog the early church. He began immediately to demonstrate a powerful understanding for the scriptures from the Prophets and other Old Testament writings. He used his established position as a Pharisee to leverage opportunity to speak in the local synagogues, where he declared Jesus to be the Son of God.
Saul the persecutor became Paul the Apostle. His conversion is even cited as one of the largely held evidences supporting the historical truth of the resurrection of Jesus. He would go on to write the majority of the New Testament, and his disciple Luke would write most of the rest. Not everyone makes the impact in life that he made, but when Jesus saves us we do change.