Śrīla Prabhupāda said:
This process is recommended in all the scriptures of the Vedic literature, it was taught by Lord Caitanya and followed by His disciplic succession for the last five hundred years, and people are achieving good results from it today, not only in India but here also. If you try to understand what this Krsna consciousness movement is, you’ll understand how transcendental meditation is possible. We are not sentimentalists; we have many books: Bhāgavad Gītā As It Is, Śrīmad Bhāgavatam, Teachings of Lord Caitanya, Śrī Īśopaniṣad. And we have our magazine, Back to Godhead. It is not that we are sentimentalists. We are backed up by high philosophical thought. But if you take up this simple process–chanting Hare Krsna, Hare Krsna, Krsna Krsna, Hare Hare/ Hare Rama, Hare Rama, Rama Rama, Hare Hare–you are immediately elevated to the transcendental platform, even without reading so much philosophical literature. This Hare Krsna mantra is Lord Caitanya Mahaprabhu’s gift to the conditioned souls of the present age, in accordance with the Vedic sanction.
The Journey of Self-Discovery-His Divine Grace A.C. Bhaktivedanta Swami Prabhupāda