What does Acts 22:15 mean?

The mob that moments ago tried to kill Paul is still listening politely to his account of the events that led him to follow Jesus. At least part of the mob thinks Paul brought a Gentile into the temple (Acts 21:27–29, 33–34). It is true that Paul came to Jerusalem with several Gentiles and has been with them since, but he would never break the Mosaic law—or the Roman law—that prohibits Gentiles from the temple. He tells his story to try to explain why he, a devout Jew trained by Gamaliel to be a proper Pharisee, now travels with Gentiles: Jesus told him to.

On his way to arrest Christ-followers in Damascus, Paul encountered Jesus in a bright light that left him blind. After fasting for three days, a Gentile Jesus-follower named Ananias visited Paul and led him through the final steps to faith in Christ. When Jesus called Ananias to go to Paul, He told the man that Paul would bring Jesus' name "before the Gentiles and kings and the children of Israel" (Acts 9:15). Paul did so. Everywhere he traveled, he started either in the local synagogue (Acts 13:14–44; 14:1; 17:1–2, 10; 18:4) or, if there was none, the place the God-followers met (Acts 16:13). Invariably, some Jews and many God-fearing Gentiles believed his message about Jesus; but those Jews who didn't believe drove him away from the synagogue. Paul would find a new place to meet, build the church, and move on to the next city, thus fulfilling Jesus' word he would reach Jews and Gentiles. In three years' time, while under house arrest in Caesarea Maritima, Paul will tell his story to Herod Agrippa II, thus preaching to a king (Acts 26).

Throughout Paul's ministry, he typically starts by teaching how Jesus fulfills the Jewish prophecies or how He brings the kingdom of God. Many Gentiles and some Jews believe. Sometimes, however, Paul leads with his own conversion story. He did so when he first arrived in Jerusalem, at the same time he met Barnabas (Acts 9:27). And he will do so when he speaks with Agrippa (Acts 26:2–23). Sometimes, to tell Jesus' story is to tell our own.