John Piper - The Happiness of God: Foundation for Christian Hedonism

Christian Hedonism teaches that the desire to be happy is God-given and should not be denied or resisted but directed to God for satisfaction. Christian Hedonism does not say that whatever you enjoy is good. It says that God has shown you what is good and doing it ought to bring you joy (Micah 6:8). And since doing the will of God ought to bring you joy, the pursuit of joy is an essential part of all moral effort. If you abandon the pursuit of joy (and thus refuse to be a Hedonist, as I use the term), you cannot fulfill the will of God. Christian Hedonism affirms that the godliest saints of every age have discovered no contradiction in saying, on the one hand, "We are being killed all the day long; we are regarded as sheep to be slaughtered" (Romans 8:36), and on the other hand, "Rejoice in the Lord always, and again I will say, Rejoice" (Philippians 4:4). Christian Hedonism does not join the culture of self-gratification that makes you a slave of your sinful impulses. Christian Hedonism commands that we not be conformed to this age but that we be transformed by the renewing of our minds (Romans 12:2) so we can delight to do the will of our Father in heaven. According to Christian Hedonism joy in God is not optional icing on the cake of Christianity. When you think it through, joy in God is an essential part of saving faith.