Exodus
Chapters 17:13-16
Revised Version 1885
13And Joshua discomfited Amalek and his people with the edge of the sword.
14And the Lord said unto Moses, Write this for a memorial in a book, and rehearse 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 Jehovah-nissi:
16and he said, The Lord hath sworn: the Lord will have war with Amalek from generation to generation.