In the Book of Acts, the author Luke gives us limited details about what Saul did in the years after his conversion. It is not the full picture of everything that happened, just enough to give us an idea of how he spent his time and to confirm that his conversion was genuine. Drawing together what he reports as well as details from the letters of Paul (Galatians 1:1–24; 2 Corinthians 11:1–33), we can confirm the following regarding the early years of Saul’s Christian life.
After Saul was baptised, he joined the church in Damascus. He spent a lot of time with believers in the city, talking about Jesus, learning more about his life and death. He also engaged with Jews in the local synagogues. At the synagogue, we would be welcomed (at least to begin with), and he would be given a chance to read a passage of Scripture and preach on the same. This is what Saul did after his conversion. Week by week, he testified before everyone, that he met with the resurrected Christ and he proclaimed him to be the Son of God.
At some point in time, Saul decided to go to Arabia. This trip is something of a mystery. We are not sure why he went into this region. Possibly it was a chance to meditate and prepare himself for ministry, following the example of Jesus and John the Baptist. More likely he was simply trying to reach out to Jews and Gentiles in the area. Why else would he incur the wrath of the Arabic king? Whatever the case may be, eventually he does go back to Damascus and over the course of a year or so, he is very active in the city.
When enough Jews in Damascus become agitated and frustrated with Saul, they make a plan to kill him and he is forced to flee. He travels to Jerusalem where he will stay for about two weeks. During this time, he is introduced to Peter and James. He also goes to visit the Greek speaking Jews who killed Stephen. Coming from Tarsus, he had a lot in common with them and he is well prepared to engage in debate. When these Jews make plans to kill him, Saul is shipped back home to Tarsus. He will stay there for around five years before Barnabas asks him to help the church in Antioch.
19 and taking food, he was strengthened.