The following articles come from a book by James Montgomery Boice, Acts: An Expositional Commentary (Grand Rapids, MI: Baker Books, 1997), 319–326.
Ephesus was so strategic that it is surprising that Paul had not gone there before, especially since he had already been in the Roman province of Asia, where Ephesus was located. The reason, as we have already seen, is that the Holy Spirit had stopped him from doing so, having had other work for him to do first.
Ephesus was a port city. Today the port is silted up and Ephesus is located three or four miles inland from the present coastline. When the port silted up, Ephesus lost its commercial advantage. But at the time Paul was there, the city was at the height of its glory. It had about one-third of a million people, which for an ancient city was a large population. It had a theater, which has been excavated and which I have seen. The theater seated twenty-five thousand people. The Rosebowl in Los Angeles seats about one hundred thousand people, so this was about one fourth of that size.
Then, too, Ephesus was noted for its magnificent temple of Diana, or Artemis. The temple of Diana was known as one of the wonders of the ancient world. It was lost to history for a time, twenty-five feet beneath the surface of the ground because of destruction and rebuilding at that site over the centuries. But in Paul’s day it was in full beauty and at the height of its influence. It was as extensive as a football field, and it was the center of much superstitious religion and cult prostitution, which was common at such temples.
Ephesus is mentioned first among the seven churches of Revelation. Its leading position probably means that among the seven important cities addressed—all of which were outstanding for one reason or another—Ephesus was of first rank.
Paul’s goals were to preach, establish churches, and use the churches for further outreach. In achieving these goals in Ephesus we see Paul’s typical urban strategy at work, just as previously in other cities. He made initial contact, worked with others, taught, and followed up.