God speaks of destroying Amalek as if he were removing people's memory of Amalek. When a group of people is completely destroyed, there is nothing to remind people about them. AT: "I will completely destroy Amalek" (See: [[rc://en/ta/man/translate/figs-metaphor]])
People would raise their hand when they made a promise or pledge, so raising the hand represents making a promise. AT: "a promise was made" (See: [[rc://en/ta/man/translate/figs-metonymy]])
This can be stated in active form. AT: "Yahweh lifted up his hand" or "Yahweh made a solemn promise" (See: [[rc://en/ta/man/translate/figs-activepassive]])