"Remember what Amalek did to you"—Deuteronomy 25:17.
We are enjoined to remember that which Amalek did to us, that they were the first to "greet" us [after we left Egypt] with evil [i.e., battle]. We must verbally recall this at all times, and awaken our souls to battle them. We must call upon people to hate them, so that the matter not be forgotten, and the hate should not abate with the passage of time.