"These things I have spoken to you, that my joy may be in you, and that your joy may be full." John 15:11
When asked why he rejected Christianity, Friedrich Nietzsche answered, "I never saw the members of my father's church enjoying themselves."
"We all know the value of joy. It alone is the proof that what we have really satisfies the heart. As long as duty or self-interest or other motives influence me, men cannot know what the object of my pursuit or possession is really worth to me. But when it gives me joy, and they see me delight in it, they know that to me at least it is a treasure. Hence there is nothing so attractive as joy, no preaching so persuasive as the sight of hearts made glad. . . . There is no proof of the reality of God's love and the blessing he bestows, which men so soon feel the force of, as when the joy of God overcomes all the trials of life."
Andrew Murray, Abide In Christ, pages 173-174.