Exodus 17:9-11

Thomson(i) 9 upon which Moses said to Joshua, Select for thyself able men and go out and draw up in array to-morrow against Amalek; when lo I have stood on the top of that hill with the staff of God in my hand. 10 So Joshua did as Moses commanded him. And when he had gone out and drawn up in array against Amalek, and Moses and Aaron and Hur had gone up to the top of the hill, 11 it came to pass that when Moses held up his hands Israel prevailed; but when he let down his hands Amalek prevailed.