A challenge from Peter Kreeft:
No one who ever said to God, “Thy will be done,” and meant it with his heart, ever failed to find joy–not just in heaven, or even down the road in the future in this world, but in this moment at every moment. Every other Christian who has ever lived has found exactly the same thing in his own experience. It is an experiment that has been performed over and over again billions of times, always with the same result.
Try it for yourself.