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.
And the Lord said unto Moses,.... After the battle was over, and the Israelites had got the victory:
Write this for a memorial in a book: not in loose papers, but in a book, that it might continue; meaning that the account of this battle with Amelek should be put down in the annals or journal of Moses, in the book of the law he was writing, or was about to write, and would write, as he did, see Joshua 1:7 that so it might be kept in memory, and transmitted to the latest posterity; it being on the one hand an instance of great impiety, inhumanity, and rashness, in Amalek, and on the other a display of the goodness, kindness, and power of God on the behalf of his people: and
rehearse it in the ears of Joshua; who was a principal person concerned in this battle, and therefore, when the account was written and rehearsed, could bear witness to the truth of it, as well as he was to be the chief person that should be concerned in introducing the Israelites into the land of Canaan, and subduing the Canaanites; and therefore this, and what follows, was to be rehearsed to him, as the rule of his conduct toward them, and particularly Amalek:
for I will utterly put out the remembrance of Amelek from under heaven; so that they shall be no more a nation, and their name never mentioned, unless with disgrace and contempt. This was fulfilled partly by Saul,
1 Samuel 15:8 and more completely by David, 1 Samuel 30:17, and the finishing stroke the Jews give to Mordecai and Esther, as the Targum of Jerusalem on Exodus 17:6.