So Joshua did as Moses said to him, and fought with Amalek. And Moses, Aaron, and Hur went up to the top of the hill.
Exodus 17:10
Surrounding context
17:9 And Moses said to Joshua, "Choose us some men and go out, fight with Amalek. Tomorrow I will stand on the top of the hill with the rod of God in my hand."
17:10 So Joshua did as Moses said to him, and fought with Amalek. And Moses, Aaron, and Hur went up to the top of the hill.
17:11 And so it was, when Moses held up his hand, that Israel prevailed; and when he let down his hand, Amalek prevailed.