1 Samuel 29:9-11

Achish answered David, “I know that you are blameless in my sight, like an angel of God; nevertheless the commanders of the Philistines have said, ‘He must not go up with us to the battle.’ So now, get up early in the morning with your master’s servants who have come with you, and as soon as you are up in the morning and have light, leave.” So David and his men got up early to leave in the morning, to return to the land of the Philistines. But the Philistines went up to Jezreel [to fight against Israel].