What does Acts 19:29 mean?
In Athens, Gentiles rejected Paul's offer of salvation on the grounds of philosophical differences: they didn't believe in the resurrection of the dead (Acts 17:32). In Philippi and Ephesus, it's because Paul's ministry threatens a small group's ability to make money (Acts 16:19; 19:26–27). In Ephesus, so many people are abandoning the Greek gods and following Jesus that the craftsmen who make idols are losing business. To remind the Ephesians of their regional heritage, and drum up more business, the craftsmen start a protest in support of Artemis (Acts 19:28).The people of Ephesus don't know what's going on (Acts 19:32). They just know Demetrius, a silversmith, has dragged two men from Macedonia into the theater. The theater is carved into a mountain slope and can hold 24,000 people. Three times a month the people meet there to discus and vote on issues. This is not one of those times.
Gaius is from Corinth and hosted Paul during his first visit (Romans 16:23). Third John 1:1 mentions a Gaius, and it would make sense if this was the same Gaius since John lived in Ephesus and his letter is about hospitality. However, this is not the same Gaius mentioned in Acts 20:4, who was from Derbe.
Aristarchus, from Thessalonica, remains Paul's companion for a while. He travels with Paul from Ephesus to Greece and Jerusalem where they both are arrested. Aristarchus is also imprisoned with Paul in Rome, although it seems he is freed before Paul (Acts 20:4; 27:2; Colossians 4:10; Philemon 1:24).
Fortunately, the town clerk can disperse the riot (Acts 19:41). Even so, Paul is rattled. He will write to the church in Corinth, "For we do not want you to be unaware, brothers, of the affliction we experienced in Asia. For we were so utterly burdened beyond our strength that we despaired of life itself. Indeed, we felt that we had received the sentence of death. But that was to make us rely not on ourselves but on God who raises the dead" (2 Corinthians 1:8–9). As soon as everyone is safe, Paul leaves for Troas and Macedonia (Acts 20:1).