1 Samuel 27:10-12

10“Where did you make your raid today?” Achish would ask. And David would reply, “Against the south of Judah, the Jerahmeelites, and the Kenites.”

11No one was left alive to come to Gath and tell where he had really been. This happened again and again while he was living among the Philistines.

12Achish believed David and thought to himself, “By now the people of Israel must hate him bitterly. Now he will have to stay here and serve me forever!”