There are two men named Demetrius in the Bible: 1) a rabble-rousing silversmith in Acts 19:23–41, and 2) a Christian of good repute in 3 John 1:12.
The Demetrius whom John mentions in 3 John is likely the man who delivered the epistle to Gaius, the recipient. John says that Demetrius is well-known for his commitment to the truth and has well-deserved praise from all who know him.
This rest of this article will concentrate on the more prominent Demetrius, found in Acts. This Demetrius was a silversmith who made his livelihood from making silver shrines of Ephesus’ famous temple of Diana (Artemis). These small shrines were sold to tourists who were told they could take the shrine anywhere in the world and worship Artemis just like they would in her temple in Ephesus. These silver shrines are thought to have been a cupped enclosure with a small female figure inside.
Paul spent years in Ephesus (Acts 19:10), and his ministry began impacting people for Christ. God performed extraordinary miracles through Paul (Acts 19:11). As the gospel began changing lives, the followers of Artemis noticed.
Demetrius noticed, too. Sales of his idolatrous shrines were falling off. He became concerned that Paul’s teaching would put an end to his business. If people began worshiping the true God, they would no longer want his idols of Artemis. Demetrius gathered the tradesmen of Ephesus and said, “You know, my friends, that we receive a good income from this business [selling Artemis shrines]. And you see and hear how this fellow Paul has convinced and led astray large numbers of people here in Ephesus and in practically the whole province of Asia. He says that gods made by human hands are no gods at all. There is danger not only that our trade will lose its good name, but also that the temple of the great goddess Artemis will be discredited; and the goddess herself, who is worshiped throughout the province of Asia and the world, will be robbed of her divine majesty” (Acts 19:25–27). While Demetrius claimed his motivation for opposing Paul was to defend the “majesty” of Artemis, his true motivation seems to have been less altruistic. We can speculate that his real motivation was his profit margin.
Demetrius and the other craftsmen took to the streets, stirring up a crowd of Artemis-worshipers and starting a riot. Paul’s companions Gaius and Aristarchus were captured by the crowd and taken to the theater in Ephesus (Acts 19:29). The frenzied mob shouted chants of praise to Artemis in the theater for two hours straight (verse 34). Finally, the city clerk gained an audience and reminded Demetrius that the proper place for him to air his grievances was in court. He then told the mob they were breaking Roman law by disturbing the peace. The rioters dispersed after that (verse 41).
After the commotion caused by Demetrius, Paul left Ephesus for Macedonia (Acts 20:1). The Bible does not mention Demetrius again, although the Alexander mentioned in Acts 19:33 is thought by some to be the coppersmith Paul mentions in 2 Timothy 4:14.