What does Acts 10:22 mean?
Peter is in Joppa, near modern-day Tel Aviv, at the home of Simon the Tanner. Three strangers have come to the gate, and the Holy Spirit tells Peter to greet them, as God has sent the men to him. When Peter asks, they explain why they are there.Judaism is a mysterious enigma in the Roman Empire. Unlike other faiths, Jews have no physical representations of their God—no idols or statues. With nothing to see or touch, many Romans classify Jews as "atheists." Others find their religion mysterious and exotic. Jewish charlatans take advantage of this. For example, Elymas, a Jewish false prophet, bills himself as a magician and captivates Sergius Paulus, the proconsul of Salamis on Cyprus. When Paul and Barnabas see him, Paul soundly condemns Elymas and Sergius Paulus believes in Jesus (Acts 13:4–12).
But there are two other types of Roman interest in Judaism. The most extreme leads Gentiles to fully renounce their original religion, accept circumcision for males, and follow the Mosaic law as strongly as any native-born Jew. Some of these proselytes were in the crowd on the day of Pentecost (Acts 2:7–11); Old Testament examples include Rahab and Ruth. Just a step down from proselytes are the "devout" or "God-fearing," although those terms may sometimes be used for proselytes as well. "Devout" Gentiles worship the Jewish God but do not accept circumcision. Cornelius is such a man, as is the soldier he sent with his two servants to find Peter (Acts 10:1–8).
The Holy Spirit didn't tell Cornelius what Peter will say, nor does He directly tell Peter what to say. When Cornelius repeats his story (Acts 10:30–33) and shows his humility to listen to and accept whatever Peter has to say, Peter seems to remember what Jesus said right before His ascension: they will be His witnesses to the ends of the earth. So that is what Peter does: give his witness of Jesus to these foreigners from far away.