Life is war. That’s not all it is. But it is always that. Our weakness in prayer is owing largely to our neglect of this truth. Prayer is primarily a wartime walkie-talkie for the mission of the Church as it advances against the powers of darkness and unbelief. It is not surprising that prayer malfunctions when we try to make it a domestic intercom to call upstairs for more comforts for the den. God has given us prayer as a wartime walkie-talkie so that we can call headquarters for everything we need as the kingdom of God advances in the world. Prayer gives us the significance of front-line forces, and gives God the glory of a limitless Provider. The one who gives the power gets the glory. Thus prayer safeguards the supremacy of God in missions while linking us with endless grace for every need.
John Piper
From the book “Let The Nations Be Glad”