What does Acts 16:38 mean?

The Roman Empire was built on a multilayered caste system. Beyond the levels of patrician, equestrian, plebeian, freedman, and slave, there were citizens and non-citizens. People could be born citizens if they were from a Roman colony or their parents were citizens. They could earn it by accomplishing a significant honor for the Empire or by purchasing it. Citizenship accorded many advantages including the right to appeal a verdict (Acts 25:11) and the right to a fair trial before being punished.

It is this last civil right which has the Philippian magistrates frightened. Two itinerant Jewish teachers, Paul and Silas, have been teaching people to worship another Jewish man, Jesus of Nazareth. Not only is it a crime to worship a god that is not authorized by the Roman Empire, but also no mere man can be placed in a position of authority over Caesar. The magistrates let a crowd attack Paul and Silas, then order them beaten with rods and imprisoned for one night. As was the custom, the magistrates planned on exiling the missionaries from Philippi in the morning (Acts 16:21–24, 35).

The crime the magistrates have committed seems to be a greater legal offense than that of Paul and Silas. Years later, a tribune of the Roman army will have the same response of fear when he realizes his troops have merely tied Paul up (Acts 22:29).

Paul and Silas are not vindictive. They don't want to punish the magistrates; they just want a formal apology. The magistrates comply, and Paul and Silas bid farewell to their hostess Lydia and leave town (Acts 16:39–40).