Exodus 17:12 - Exposition

But Moses' hands were heavy . Moses, no doubt, held the rod alternately with one hand and the other, until both were so tired that he could hold them up no longer. It is this natural weariness which is expressed by the words—"his hands were heavy." When Aaron and Hut perceived this, they brought a stone for him to sit on, and then, standing one on either side of him, alternately supported his hands until the sun set and the battle was over. To reward the faith and perseverance of the three, God gave Israel in the end a complete victory.