Exodus 17:9

17:9 So Moses said to Joshua, “Choose some of our men and go out, fight against Amalek. Tomorrow I will stand on top of the hill with the staff of God in my hand.”

Exodus 24:13

24:13 So Moses set out with Joshua his attendant, and Moses went up the mountain of God.

Exodus 32:17

32:17 When Joshua heard the noise of the people as they shouted, he said to Moses, “It is the sound of war in the camp!”