What does Acts 15:12 mean?

Paul and Barnabas had a successful, if somewhat harrowing, missionary journey up into central modern-day Asia Minor. They established several churches in the region of Galatia and watched many Gentiles come to a saving faith in Jesus (Acts 13—14). Upon their return to their home church in Syrian Antioch, they were accosted by Jewish Christians from the sect of the Pharisees. The visitors insisted that Gentiles needed to be circumcised and follow the Mosaic law to be saved.

This assertion contradicted Paul and Barnabas' experience and understanding of the gospel: that salvation is by grace, not works. The pair, along with other representatives from Syrian Antioch, traveled to Jerusalem to request a judgment by the apostles and church leaders. In part, this is because the Pharisees came from that area, and they may have been claiming to have the authority of the Jerusalem church (Galatians 2:12; Acts 15:24). Another reason is that the leaders in Jerusalem had learned either directly from Jesus or from those who had, and their endorsement would be vital when the issue arose again.

In Jerusalem, Paul and Barnabas give their story, but more Pharisee-Christians take up a cry against them. The formal council discusses the issue. A long debate ensues before Peter stands and reminds the council of his experience with Cornelius. He witnessed a Roman centurion and a houseful of Gentiles receive the Holy Spirit without circumcision, Law, or even baptism. Peter finishes by affirming that even Jews can't follow the Mosaic law; salvation for everyone—Jew and Gentile—is through grace (Acts 15:4–11).

Now, Barnabas and Paul present their official testimony. They recount a list of the miracles they were able to perform during their journey. Specifically, Paul blinded a Jewish false prophet (Acts 13:11), healed a man crippled from birth (Acts 14:8–10), and survived being stoned (Acts 14:19–20). With Barnabas as his second witness, the council sees the miracles for what they are: affirmations. The words shared with the Gentiles were true and their work was empowered by the Holy Spirit. Undoubtedly, their testimony includes the Holy Spirit coming to the Gentiles (Acts 13:48–49; 14:1).

Next, James, the half-brother of Jesus and pastor of the church in Jerusalem, will make his determination. Faced with the accounts given by Peter, Barnabas, and Paul, the decision seems easy. He agrees that Gentiles don't have to become Jewish to follow Jesus (Acts 15:13–21). But this only seems obvious with the benefit of 2000 years of hindsight. We owe a debt of gratitude to the early church leaders who wrestled with then-new theological concepts which we can now take for granted.