CC Ādi 9.48
phalāsvāde matta loka ha-ila sakala
Here the wonderful fruit of love of Godhead distributed by Lord Caitanya Mahāprabhu is described. We have practical experience that anyone who accepts this fruit and sincerely tastes it immediately becomes mad after it and gives up all his bad habits, being intoxicated by Caitanya Mahāprabhu’s gift, the Hare Kṛṣṇa mahā-mantra. The statements of Śrī Caitanya-caritāmṛta are so practical that anyone can test them. As far as we are concerned, we are most confident of the success of the distribution of the great fruit of love of Godhead through the medium of chanting the mahā-mantra — Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare.