1 Samuel 27:8-12

8David and his men went up and raided the Geshurites, the Girzites, and the Amalekites. From ancient times they had been the inhabitants of the region through Shur as far as the land of Egypt.

9Whenever David attacked the land, he did not leave a single person alive, either man or woman, but he took flocks, herds, donkeys, camels, and clothing. Then he came back to Achish,

10who inquired, “Where did you raid today?” David replied, “The south country of Judah,” “The south country of the Jerahmeelites,” or “The south country of the Kenites.”

11David did not let a man or woman live to be brought to Gath, for he said, “Or they will inform on us and say, ‘This is what David did.’” This was David’s custom during the whole time he stayed in the Philistine territory.

12So Achish trusted David, thinking, “Since he has made himself repulsive to his people Israel, he will be my servant forever.”