Acts 22:24-26
22:24 the commanding officer ordered Paul to be brought back into the barracks. He told them to interrogate Paul by beating him with a lash so that he could find out the reason the crowd was shouting at Paul in this way.
22:25 When they had stretched him out for the lash, Paul said to the centurion standing nearby, “Is it legal for you to lash a man who is a Roman citizen without a proper trial?”
22:26 When the centurion heard this, he went to the commanding officer and reported it, saying, “What are you about to do? For this man is a Roman citizen.”