1 Samuel 17:3

And the Philistines stood on a mountain on the one side, and Israel stood on a mountain on the other side, &e.] Before the Israelites are said to encamp in or by the valley; but here they are said to take the higher ground, and face the Philistines, who were on a mountain or hill on the other side over against them, which Kimchi reconciles thus; the whole or the grand army lay encamped in the valley, and, they that were set in array, or the first ranks, the first battalion, ascended the mountain to meet the Philistines.