While the Israelites are still at Rephidim in the wilderness, they face another trial of a different kind. This time they are attacked by the Amalekites. This was the first time they encountered a military force to fight against in battle. The Amalekites were most likely descendants of Amalek, the grandson of Esau. This will not the last time that Israel will battle these desert-dwelling people. In our text we are introduced to Joshua and Hur the son of Caleb. Joshua’s appearance in this battle foreshadows his role in taking the Promised Land. The description of the battle is brief, but amazing – Moses said to Joshua “Choose for us men, and go out and fight with Amalek. Tomorrow I will stand on the top of the hill with the staff of God in my hand.” So Joshua did as Moses told him, and fought with Amalek, while Moses, Aaron, and Hur went up to the top of the hill. Whenever Moses held up his hand, Israel prevailed, and whenever he lowered his hand, Amalek prevailed. But Moses’ hands grew weary, so they took a stone and put it under him, and he sat on it, while Aaron and Hur held up his hands, one on one side, and the other on the other side. So his hands were steady until the going down of the sun. And Joshua overwhelmed Amalek and his people with the sword. (Ex 17:9-13)
Joshua and his men are told to physically fight the battle while Moses, Aaron and Hur go up to the hill with the staff of God in Moses’ hand. This was the same staff of God used to turn the waters in the Nile to blood and other plagues upon Egypt; the same staff of God used when Moses stretched out his hand to part the Red Sea. Now the staff is lifted upwards to intercede for the battle below. Through Moses and this staff the Lord is working to win the battle and defeat the Amalekites. We see this by what follows: Then the Lord said to Moses, “Write this as a memorial in a book and recite it in the ears of Joshua, that I will utterly blot out the memory of Amalek from under heaven.” And Moses built an altar and called the name of it, The Lord Is My Banner, saying, “A hand upon the throne of the Lord! The Lord will have war with Amalek from generation to generation” (Ex 17:14-16). It is the Lord who will defeat the Amalekites! Moses built a memorial stone and called it “The Lord is my banner,” because he attributed the victory unto Yahweh!