Deuteronomy 25:19 in the King James Version
Therefore it shall be, when the LORD thy God hath given thee rest from all thine enemies round about, in the land which the LORD thy God giveth thee for an inheritance to possess it, that thou shalt blot out the remembrance of Amalek from under heaven; thou shalt not forget it.
Context
18 how he met you by the way, and struck the rearmost of you, all who were feeble behind you, when you were faint and weary; and he didn’t fear God.
19 Therefore it shall be, when the LORD your God has given you rest from all your enemies all around, in the land which the LORD your God gives you for an inheritance to possess it, that you shall blot out the memory of Amalek from under the sky. You shall not forget.