1 Samuel 29:4-6

4But the Philistine commanders were angry with Achish and said, “Send the man back, that he may return to the place you assigned him. He must not go with us into battle, or he will turn against us during the fighting. How better could he regain his master’s favor than by taking the heads of our own men? 5Isn’t this the David they sang about in their dances: “ ‘Saul has slain his thousands, and David his tens of thousands’?” 6So Achish called David and said to him, “As surely as the Lord lives, you have been reliable, and I would be pleased to have you serve with me in the army. From the day you came to me until today, I have found no fault in you, but the rulers don’t approve of you.