God’s will is like a train whereas our prayer is like the rails of a train. A train may travel to any place, except that it must run on rails. It has tremendous power to go east, west, south and north, but it can only run to places where rails have been laid. So that it is not because God has no power (He, like a train, has power, great power); but because He chooses to be governed by man’s prayer, therefore all valuable prayers (like a train’s rails) pave the way for God. Consequently, if we do not take up the responsibility of prayer, we will hinder the fulfillment of God’s will.

 – Watchman Nee