Now the great idea that is here suggested to us connects this Divine joy with strength--the joy is an inspiration of energy. By the nature of things joy is exhilarating, while pain is depressing. Physiologists recognise it as a law of animal organisms that happiness is a nerve tonic. It would seem that the same law obtains in spiritual experience. On the other hand, nothing is more certain than that there are enervating pleasures, and that the free indulgence in pleasure generally weakens the character; with this goes the equally certain truth that men may be braced by suffering, that the east wind of adversity may be a real stimulant. How shall we reconcile these contradictory positions? Clearly there are different kinds and grades of delight, and different ways of taking and using every form of gladness. Pure hedonism cannot but be a weak system of life. It is the Spartan, not the Sybarite, who is capable of heroic deeds. Even Epicurus, whose name has been abused to shelter low pleasure-seeking, perceived, as clearly as "The Preacher," the melancholy truth that the life that is given over to the satisfaction of personal desires is but "vanity of vanities." The joy that exhilarates is not sought as a final goal. It comes in by the way when we are pursuing some objective end. Then this purest joy is as far above the pleasure of the self-indulgent as heaven is above hell. It may even be found side by side with bodily pain, as when martyrs exult in their flames, or when stricken souls in more prosaic circumstances awake to the wonderful perception of a rare Divine gladness. It is this joy that gives strength. There is enthusiasm in it. Such a joy not being an end in itself is a means to a great practical end. God's glad children are strong to do and bear His will, strong in their very gladness.