Exodus 17:16
King James Version
“For he said, Because the LORD hath sworn the LORD war with Amalek from generation to generation.”
Context
13And Joshua discomfited Amalek and his people with the edge of the sword.
14And the LORD said unto Moses, Write this a memorial in a book, and rehearse in the ears of Joshua: for I will utterly put out the remembrance of Amalek from under heaven.
15And Moses built an altar, and called the name of it Jehovah-nissi:
16For he said, Because the LORD hath sworn the LORD war with Amalek from generation to generation.