Exodus 17:9 WEB

⁷  He called the name of the place Massah,{Massah means testing.} and Meribah,{Meribah means quarreling.} because the children of Israel quarreled, and because they tested Yahweh, saying, 'Is Yahweh among us, or not?'

⁸  Then Amalek came and fought with Israel in Rephidim.

⁹  Moses said to Joshua, 'Choose men for us, and go out, fight with Amalek. Tomorrow I will stand on the top of the hill with God's rod in my hand.'

¹⁰  So Joshua did as Moses had told him, and fought with Amalek; and Moses, Aaron, and Hur went up to the top of the hill.

¹¹  It happened, when Moses held up his hand, that Israel prevailed; and when he let down his hand, Amalek prevailed.