Lecture on Mahā-mantra.

[In this Age of Kali there is no other means, no other means, no other means for self-realization than chanting the holy name, chanting the holy name, chanting the holy name of Lord Hari.]

If you want to realize the Supreme Truth, then you must chant this: Hare Kṛṣṇa, Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare / Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare, whenever you get... Harer nāma harer nāma harer nāma eva kevalam: "Only this." And if you think, "Oh, only this? Why not other?" No. Kalau nāsty eva nāsty eva nāsty eva gatir anyathā. Nāsty eva means "There is no alternative." And He repeats this: "no alternative, no alternative, no alternative," three times. Three times. That means He is giving too much stress.

So our process is like that, that we are following a great personality, Lord Śrī Caitanya Mahāprabhu. He introduced... He introduced from the scripture, not in His own way.

https://vedabase.io/en/library/transcripts/660909le-new-york/