Shemot 17:11-13

Orthodox Jewish Bible

¹¹ And it came to pass, as long as Moshe held up his yad, that Yisroel prevailed; and when he let down his yad, Amalek prevailed.

¹² When the hands of Moshe grew heavy, they took an even (stone), and put it under him, and he sat thereon; and Aharon and Chur supported his hands, the one on the one side, and the other on the other side; and his hands held emunah (steady) until bo hashemesh (sunset).

¹³ And Yehoshua disabled Amalek and his army with the edge of the cherev.