Exodus 17:8-12

8Then 1Amalek came and fought against Israel at 2Rephidim.

9So Moses said to 3Joshua, “Choose men for us and go out, fight against Amalek. Tomorrow I will station myself on the top of the hill with 4the staff of God in my hand.”

10Joshua did just as Moses 5told him, 6and fought against Amalek; and Moses, Aaron, and 7Hur went up to the top of the hill.

11So it came about, when Moses held his hand up, that Israel prevailed; but when he let his hand 8down, Amalek prevailed.

12And Moses’ hands were heavy. So they took a stone and put it under him, and he sat on it; and Aaron and Hur 9supported his hands, one on one side and one on the other. So his hands were steady until the sun set.