This point in Acts marks a significant and substantial change in the world view of the newly formed church.
God had appeared hundreds of years before to Abraham and had promised him more descendants than could be numbered and that through him all the nations of the world would be blessed. The Old Testament recorded numerous repetitions of the covenant and prophecies of the coming Messiah. The Jews knew that they were the specially chosen people of God. In accordance with God’s promises Jesus came as a Jew and concentrated much of his ministry on the Jews. Jesus commissioned His disciples to go to Jerusalem, Judea and the ends of the Earth. Pentecost saw the church birthed with thousands of Jews accepting Jesus. The church began to grow and when persecution came the believers were dispersed. God supernaturally intervened to send Peter to Cornelius and show that the gospel was also for the Gentiles. Paul and Barnabas, as well as other disciples, went out and whilst they still started with the Jewish synagogues the Gentiles heard the gospel and believed in great numbers.
Reports of the growth of the gospel amongst the Gentiles came back to the church in Jerusalem and they faced an awesome decision: Was Christianity a sect of Judaism such that the new believers in the gospel also became proselytised Jews? Or was it a new belief system with its own norms and practises? The resolution was to accept that although God was doing a new thing, His character had not changed, merely the nature of His relationship with His new people. The pattern now adopted by Paul was usually to start by going to win over the Jews, but if that was unfruitful they were free to reach out to the Gentiles too. Before long, Paul would be able to write that within the new church there is no longer Greek (Gentile) or Jew but one new man in Christ. (Eph 2:15)
The Apostles and early believers who had seen (correctly) that Jesus was the promised Jewish Messiah now had their hearts and eyes opened to the full truth of God’s promise to Abraham that through him ALL the nations would be blessed. Henceforth the mark of what it meant to be part of God’s chosen people was not a physical change (circumcision) but an inward change (faith in Christ and receiving the Holy Spirit). Piety was no longer obedience to hundreds of rules and rituals but being guided by the Holy Spirit and loving God and others.
God changed the first believers’ view of what it meant to be part of God’s chosen people and what being a believer looked like. Are we willing to let him change our views?