11 The apostles and the believers throughout Judea heard that the Gentiles also had received the word of God. 2 So when Peter went up to Jerusalem, the circumcised believers criticized him 3 and said, “You went into the house of uncircumcised men and ate with them.”
When news gets back to the mother church in Jerusalem of the conversion of the Gentiles, at first the believers are very skeptical. After all, how could Peter eat with those "unclean" Gentiles. They were still operating under the old model that Jesus came to reach the Jews only. After all, they were the "chosen people". But when Peter recounts the story to them, they come to understand that these Gentiles have truly come to faith in Christ Jesus. Importantly, they acknowledge that even to the Gentiles has God granted repentance that leads to life. Notice it is God that grants repentance. Meaning God works in us to turn us from our old way to come to the new way through Christ.
As we see in the rest of the chapter, the persecution of Stephen led to believers going as far north as Antioch. The gospel was preached to the Greeks, and a large number of them came to faith. The Christian movement is now spreading north. The Lord's hand was with them and great number of them came to faith. God had granted favor to these new apostles, and through their faithfulness to preach the Word about Christ, the church started exploding. Eventually the church sent Barnabas to Antioch, and he affirmed that it was the grace of God that was producing all of this fruit. Then, he came back and got Saul and they stayed in Antioch for a year.
Notice two things. This is the first time the believers were called the "church", and also the first time they were called "Christians". The church now had a "beachhead" outside of Jerusalem, a sign that the church was beginning to grow as Jesus had commanded before he left to go to heaven.
What can we learn from this? One, it is clear that it was God's favor and grace that led to this movement of Greeks to come to faith. Without this these results would not have happened. Our job is to preach the gospel and go where God calls us. God's job is to grant repentance to those who hear the Gospel and turn faith in Jesus. But notice even through the persecution, the believers are faithful and it does not stop the spread of the Good News. If anything, it ignites it's spread because it shows how genuine their faith is.
We live in times where we think Christians are increasingly being persecuted by the culture around us. But could this be an "open door" for the gospel. Will we reach out to those who God is bringing us, to or sending us out to reach? We can be sure that as we are faithful to "go", God will continue to grant grace and work repentance in those who believe like we do.