Prayer for healing in Christian Science brings Truth to bear on error in human consciousness. The result is successful in the degree that this is actually done.
In silent prayer the words used serve as guides to the healer, clarifying his mental position and systematizing his attack on the error which is binding the patient. But the power that heals is the power of Truth itself. Words used properly open the door of consciousness that Truth may come in. The words themselves embody Truth in some degree. But always it is Truth that heals.
Truth sometimes comes to human consciousness without words—pure concepts of reality revealing God as the only Mind, Life, Principle, Soul, and man as God's perfect image. But more often it comes with the aid of words. Inspired passages from the Bible or from the writings of Mrs. Eddy are especially helpful in setting human thought in order so that Truth may be clearly seen and applied to the error which seems to dominate the case.