Exodus 17:14-16

Young's Literal Translation

¹⁴ And Jehovah saith unto Moses, `Write this, a memorial in a Book, and set [it] in the ears of Joshua, that I do utterly wipe away the remembrance of Amalek from under the heavens;'

¹⁵ and Moses buildeth an altar, and calleth its name Jehovah-Nissi,

¹⁶ and saith, `Because a hand [is] on the throne of Jah, war [is] to Jehovah with Amalek from generation -- generation.'