In Exodus, Brother Tim Roller speaks about the battle that Joshua faced, and how Moses chose to support him. While Joshua was fighting Amalek, Moses was praying to provide his support towards Joshua. When Moses was tired, Aaron and Hur held his hands up in prayer, to help both Joshua and Moses prevail for God.
Like Moses and Joshua, we are fighting a battle, to win souls over to God. Often, we forget that it is our responsibility to help those around us through prayer. As Christians, we should pray for our brothers and sisters in Christ, to give them strength in their battles, and protection from the enemy they face.