Exodus 17:9
And Moses said unto Joshua, Choose us out men, and go out, fight with Amalek: to morrow I will stand on the top of the hill with the rod of God in mine hand. And Moses said unto Joshua, Choose us out men, and go out, fight with Amalek: to morrow I will stand on the top of the hill with the rod of God in mine hand.
Moses sent Joshua to select soldiers and meet Amalek in open battle below, while he himself took his place on the hill above holding the rod of God. His uplifted hands were earnest prayer for Israel, so that Israel advanced when his hands were raised and lost ground when weariness let them drop, until Aaron and Hur held them steady till the victory was complete. The rod and the raised hands had no power in themselves, but showed that Israel's strength and help were in God above and not in their own force. As the people trusted Him, God took charge of their cause and fought for them, while whenever they trusted themselves they were overcome and proved weaker than those who did not know Him. Yet prayer did not excuse inaction, for Israel was to fight with all available strength and best effort, joining human endeavor to divine power.
Setting and Course of Battle
This was Amalek's first war against Israel after the coming out of Egypt, the first people to make war upon them in the wilderness. The attack was unprovoked and cruel, falling upon the weary and defenseless, and it was an act of defiance against God that brought doom upon the nation and a sentence to be later carried out. Beyond the assault itself, Amalek mocked God's deliverance of Israel and boasted that neither Israel nor its God could escape its power. God marked that defiance and appointed Amalek's destruction by the very people they had despised.
The battle came after Israel's unbelief and complaints in the wilderness, and their enemies were allowed to make war with them so they would learn that their strength came from God. Moses did not leave the outcome to chance but directed Joshua to choose men and lead them in fighting Amalek below, while he himself would stand on a nearby hill overlooking the battle with the rod of God in his hand. Joshua and his band of soldiers thus went out to fight while Moses took his place above with the rod.
Moses' raised hands toward heaven were prayer and earnest intercession for Israel's success, and victory turned with them. So long as his hands reached upward Israel prevailed and drove the enemy back, but when fatigue let them fall Amalek gained the advantage and was victorious. When Moses grew weary, Aaron and Hur stayed up and supported his hands until Israel won completely and the enemy was put to flight. That victory was given by the angels of God, principalities and powers.
Trusting God While Fighting
The rod in Moses' hand had no power in itself, and neither did his uplifted hands, but both signified Israel's dependence on God and showed the people that their strength and vitality came from above. Those hands stretched toward heaven declared to enemies and to all around that Israel's help was in God. Israel was to trust the living God who was guiding them and follow His directions, for God held Israel's destiny in His hands and was its acknowledged leader. As the people trusted Him He fought their battles and subdued their enemies. When they relied on their own power they were overcome, becoming weaker than those who did not know God and letting their enemies prevail. God's people must therefore take no glory to themselves but look to God and trust Him continually.
Divine strength was to be joined with human effort, for Israel was not to remain inactive while Moses prayed. They were to prepare and fight with the strength available to them, with their best effort and with all their strength, while Moses brought their need to God in earnest prayer and intercession above. Prayer does not replace faithful action, and faithful action without prayer does not bring victory. The lesson belongs to God's people in every age, who must look to God for help and guidance, trust Him to lead them through difficulties and overcome their enemies, and look to Him if they hope to be translated. Jesus Christ is the mighty Leader who carries His people through the wilderness.
Aaron and Hur staying up Moses' weary hands demonstrates Israel's duty to support him as he received God's word. The same applies today: as God's workers go forth into the harvest field, those who remain at home must hold up their hands by prayer for them and must not neglect to do this. At the same time they must still press the battle to the gate as though they have something to do, proving by overcoming the corruptions in the world through partaking of the divine nature that power is granted to overcome.