Exodus 17:8–16

⁸Then came Amalek and fought with Israel at Rephidim. ⁹And Moses said to Joshua, “Choose for us 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.” ¹⁰So Joshua did as Moses told him, and fought with Amalek; and Moses, Aaron, and Hur went up to the top of the hill. ¹¹Whenever Moses held up his hand, Israel prevailed; and whenever he lowered his hand, Amalek prevailed. ¹²But Moses’ hands grew weary; so they took a stone and put it under him, and he sat upon it, and 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. ¹³And Joshua mowed down Amalek and his people with the edge of the sword.

¹⁴And 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 remembrance of Amalek from under heaven.” ¹⁵And Moses built an altar and called the name of it, The Lord is my banner, ¹⁶saying, “A hand upon the banner of the Lord! The Lord will have war with Amalek from generation to generation.”