There is an important truth of which thousands of men are ignorant; or if they know it, they reflect upon it seldom, and with but little fruit. Yet the knowledge of this truth is almost as necessary for all those who have attained the age of reason, as the knowledge of the mysteries of the Trinity and Incarnation. The importance of this great truth seems to be a mystery not merely to the heathen, Jews and heretics, but even to the greater part of Christians; nay, even to many of those who have consecrated themselves to God. We often hear in sermons, and read in pious books, of the necessity of avoiding bad company, of hating sin, of forgiving injuries, and of being reconciled to our enemies; but seldom are we taught this great truth, or, if it is sometimes spoken of, it is rarely done in a manner calculated to leave upon our minds a lasting impression of its great importance and necessity. Now this important truth is, that according to the ordinary course of Divine providence, man cannot be saved without prayer.