Initially, the Christian church was mostly limited to Jerusalem, although the gospel reached people from a variety of places. When the first martyr, Stephen, died, the church started to spread.
What is the church?
The English word church goes back to the Greek ekklesia kyriake, “assembly of the Lord”. By using the word ekklesia, the New Testament reminds us of the assembly of Israelites in the Wilderness under Moses. Just as Moses gathered these ancient believers and led them to the Promised Land, so Jesus gathers believers today and leads them to their destination.
In principle, the church consists of all Christian believers worldwide. In practice we see local churches, groups of believers who gather together for worship and fellowship. The Bible speaks very highly of the church: it is the body of Jesus Christ, and his bride. It is the community in which God’s Kingdom is taken shape and the Holy Spirit is present.
Early church life
Acts 2:42ff give a short, but beautiful description of the life of the first church. “They devoted themselves to the apostles’ teaching and the fellowship, to the breaking of the bread and the prayers.” The key activities of the Christian church are proclaiming the gospel, praying to God, using the sacraments, and being a community of care and love.
We read that the early Christians gathered daily at the temple, the public centre of worship in Jerusalem. Privately they met in their homes. This was not something new, but patterned on the Jewish synagogue meetings.
Eating together (“breaking bread”) was an important activity. Later in the New Testament, they are called “love feasts” (Jude :12). A communal meal is a natural context for fellowship and celebration. During this dinner, believers would use the sacrament of the eucharist, eating bread and drinking wine in commemoration of Jesus. Finally, it gave church members to take care of the poor among them, by sharing their food and other daily necessities.
Acts reports (2:47; 5:13) that the other people in Jerusalem viewed the Christian church with respect. They admired the radical selfless lifestyle of the community, even if they were not ready to follow their example. However, the Jewish leaders did not tolerate the public preaching of the apostles. Not only did they continue Jesus’ gospel ministry, they also healed people in public as he had done. They arrested and imprisoned the apostles a few times, but with little success.
New converts
Simon the Sorcerer was an important man (“wizard”) in Samaria. The Samaritans believe Philip’s preaching about Jesus. When Simon sees the power of the Holy Spirit, he interprets it as magical power and wants to buy it. (We still use the word simony for buying an ecclesiastical office with money.)
The Ethiopian Eunuch was a foreign official, interested in Jewish religion (a “god-fearer”). After a visit to Jerusalem, he is puzzled about Isaiah’s prophecy about the “Suffering Servant”. God prompts Philip to ride with him and explain that Jesus fulfilled this prophecy. The Ethiopian man believes and is baptized.
Cornelius the Centurion was a Roman official, sympathetic to the Jews and a “god-fearer”. He invites Peter to come to his home and tell about Jesus. Peter is hesitant, because this Gentile man is “unclean”. In a vision, God teaches Peter that God makes the unclean clean. When Peter proclaims Jesus, Cornelius’ household believes and receives the Holy Spirit.
By presenting these special converts, Luke shows that the gospel cannot remain confined to Israel. It overcomes the barriers of “uncleanness”. A Samaritan sorcerer, a castrate, and a Gentile oppressor are equally welcome to the Kingdom of Jesus. These events challenge the supposed priority of Jewishness (Acts 11:1ff); eventually, this will lead to the discussion of the Jerusalem Council (Acts 15; next lesson).

Persecution and expansion
But the Jews from outside Jerusalem are more radical. When they hear Stephen talk about Jesus, they charge him with blasphemy. The accusations are the same as those against Jesus: disrespect for Jewish customs and for the temple. In response, Stephen points out that the Jews who reject Jesus are stubborn and unbelieving. Enraged, they condemn him to death and execute him.
Thus Stephen becomes the first believer who follows Jesus on the path of suffering and death. He is the first Christian martyr (lit. “witness”). After Stephen’s death, more Christians are arrested and killed for their faith.
Stephen’s death sparks more persecution of Christians. Many believers move away from Jerusalem and take the gospel with them. Unintentionally, they begin the missionary work of being witnesses even to the end of the earth.
In particular, some believers end up in Antioch of Syria. They form a church, which grows fast with many Gentile (non-Jewish) “god-fearers” joining. The leaders of the Jerusalem church, perhaps somewhat suspicious of the goings-on in Antioch, commissions Barnabas to inspect the new “church plant”. When he sees the grace of God at work, he is glad and encourages the new church. Barnabas also realizes that more work is to be done; he enlists help (from Paul) and soon Antioch becomes a centre of mission work.