1 Samuel 29:11
So David and his men rose up early to depart in the morning, to return into the land of the Philistines. And the Philistines went up to Jezreel. So David and his men rose up early to depart in the morning, to return into the land of the Philistines. And the Philistines went up to Jezreel.
David and his men got up at dawn to make their departure. Their movement was a return back into Philistine territory. Before turning back they had been marching with the Philistine army on its way toward battle. While they withdrew, the Philistines themselves advanced up to Jezreel. That leaving kept David from fighting alongside the Philistines against Israel, so he took no part in the battle.