This is the great fallacy of the Christian hedonism movement that the Baptist minister from St. Paul, John Piper has been the advocate of. Piper says that we delight in God because of what He does for us. This is crucial and the simple change makes the greatest difference in the true meaning of this vital question. There is a difference between the joy of the hypocrite and the joy of the true Saint. The joy of the hypocrite is in himself.
Self is the foundation of all the hypocrites joy.
The joy of the saint is in God. The hypocrite has as his or her primary goal the delight, privilege and happiness that is supposedly attained already. The delight of the true Saint has its mind inexpressibly pleased and delighted with the sweet ideas of the nature and attributes of God. This is the defect of Christian hedonism. The focus is upon ourselves when it comes to delighting in God.