1 Samuel 29:2
And the lords of the Philistines passed on by hundreds, and by thousands: but David and his men passed on in the rereward with Achish. And the lords of the Philistines passed on by hundreds, and by thousands: but David and his men passed on in the rereward with Achish.
As the Philistine forces advanced toward battle in companies of hundreds and of thousands, David and his men marched in the rear division together with Achish. Although present in the line of march, they took no part in the actual fighting. David was expected to fight on behalf of the Philistines, yet he could not agree to lift his sword against Israel. To abandon his assigned post would have looked like cowardice and treachery toward Achish, while to go forward into battle would have made him a traitor to his own people and to God.