Bishop Joseph Hall—an ardent seventeenth-century Anglican once imprisoned in the Tower of London for his Puritan leanings—spent his final years on a small farm in the English countryside, where he wrote devotional classics that will live forever. Here is what he said about prayer.
An arrow, if it be drawn up but a little way, goes not far; but, if it be pulled up to the head, flies swiftly and pierces deep. Thus prayer, if it be only dribbled forth from careless lips, falls at our feet. It is the strength of [discharge] and strong desire which sends it to heaven, and makes it pierce the clouds. It is not the arithmetic of our prayers, how many they are; not the rhetoric of our prayers, how eloquent they be; nor the geometry of our prayers, how long they be; nor the music of our prayers, how sweet our voice may be; nor the logic of our prayers, how argumentative they may be; nor the method of our prayers, how orderly they may be; nor even the divinity of our prayers, how good the doctrine may be;—which God cares for. Fervency of spirit is that which availeth much.