1 Samuel 29:8-9

8So David said to Achish, “But what have I done? And to this day what have you found in your servant as long as I have been with you, that I may not go and fight against the enemies of my lord the king?”

9Then Achish answered and said to David, “I know that you are as good in my sight as an angel of God; nevertheless the princes of the Philistines have said, ‘He shall not go up with us to the battle.’