1 Samuel 27:8-12

Now David and his men went up and raided the Geshurites, the Girzites, and the Amalekites [the enemies of Israel that Joshua had failed to annihilate]; for they had inhabited the land from ancient times, as one comes to Shur even as far as the land of Egypt. [Deut 25:19; Josh 13:1, 2, 13] David attacked the land and did not leave a man or a woman alive, but he took the sheep, the cattle, the donkeys, the camels, and the clothing, and returned to Achish. When Achish asked, “Where did you raid today?” David replied, “Against the Negev (the South country) of Judah, and against the Negev of the Jerahmeelites, and against the Negev of the Kenites.” David did not leave a man or a woman alive to bring news to Gath, saying [to himself], “Otherwise they will tell about us, saying, ‘This is what David has done, and this has been his practice all the time that he has lived in the country of the Philistines.’ ” Achish believed David, saying, “He has certainly become hated by his people in Israel; so he will always be my servant.”