Why did the mob riot in Ephesus in Acts?
The Ephesian mob rioted because of what the apostle Paul had been accomplishing among those pagan people. They rushed into the theater as a disorderly mob, and the gathering was called an Ekklesia, an assembly. The King James translators rendered that term assembly, not church, in this instance.
Les explains that the riot in Ephesus was another instance where the word Ekklesia appears, but the group was anything but a spiritual assembly. He says they ran into the theater as a mob and were rioting because of what the apostle Paul had been accomplishing among those pagan people. What was it called? An Ekklesia. Fortunately, the King James translators did not use the word Church there; they used Assembly. This illustrates that Ekklesia means a called-out assembly and can even describe a riotous mob. Les also notes that the Roman authorities would call them into question, so these terminologies must be handled carefully.