What city served as the home base for Paul and Barnabas's and later Paul and Silas's missionary journeys to the Gentiles?
Antioch was the city from which Paul and Barnabas were commissioned by the Holy Spirit to go to the Gentiles in western Turkey, and to which they returned. Later, Paul and Silas left from Antioch for the Gentile world and came back there. It was not Jerusalem.
Les explains that Antioch, about 150–200 miles north of Jerusalem, was the place from which Paul and Barnabas were first commissioned by the Holy Spirit to go to the Gentiles in western Turkey. It was not Jerusalem. Les notes that Antioch was the place Paul and Barnabas left and returned to, and later the place from which Paul and Silas left again to the Gentile world and came back to Antioch. He is careful not to call Antioch the headquarters of the Church, but it served as the jump-off point, showing God keeping Judaism and Christianity distinct even though connected by their beginnings.