We should pray to God “only for the love of God” not because we “fear Him or hell, or hope for bounty or heaven”

In the highest prayer, men pray only for the love of God, not because they fear Him or hell, or hope for bounty or heaven.... When a man falls in love with a human being, it is impossible for him to keep from mentioning the name of his beloved. How much more difficult is it to keep from mentioning the Name of God when one has come to love Him.... The spiritual man finds no delight in anything save in commemoration of God. (Report of 'Abdu'l-Bahá's words as quoted in J. E. Esslemont, ‘Bahá'u'lláh and the New Era’; The Compilation of Compilations, Vol. II, The Importance of Prayer, Meditation and the Devotional Attitude)