Exodus 17:10

Overview - Exodus 17
1	The people murmur for water at Rephidim.
6	God sends them for water to the rock in Horeb.
7	The place is called Massah and Meribah.
8	Amalek is overcome by Joshua, while Moses holds up his hands with the rod of God.
14	Amalek is doomed to destruction; and Moses builds the altar JEHOVAH-nissi.

Exodus 17:10  (King James Version)
So Joshua did as Moses had said to him, and fought with Amalek: and Moses, Aaron, and Hur went up to the top of the hill.