Exodus 17:14 in the King James Version
And the LORD said unto Moses, Write this for a memorial in a book, and rehearse it in the ears of Joshua: for I will utterly put out the remembrance of Amalek from under heaven.
Context
13 Joshua defeated Amalek and his people with the edge of the sword.
14 The LORD said to Moses, “Write this for a memorial in a book, and rehearse it in the ears of Joshua: that I will utterly blot out the memory of Amalek from under the sky.”
15 Moses built an altar, and called its name “The LORD our Banner”.