The Maha Mantra is a Hare Krishna or Vaishnava mantra as mentioned in the Kali-Santarana Upanishad. This mantra rose to importance in the 15th century – Bhakti movement following the teachings of Chaitanya Mahaprabhu. According to Gaudiya Vaishnava theology, one’s original consciousness and goal of life is pure love of the god Krishna. Since the 1960s, the mantra has been made well known outside India by A. C. Bhaktivedanta Swami Prabhupada and his movement, International Society for Krishna Consciousness (ISKCON).
The actual mantra in the Upanishad is as follows: Hare Rama Hare Rama Rama Rama Hare Hare Hare Kṛṣṇa Hare Kṛṣṇa Kṛṣṇa Kṛṣṇa Hare Hare. After the ISCKON movement gained popularity, it became the mahamantra for the devotees and the pattern has shifted to bring in the Krishna name first instead of Rama: Hare Kṛṣṇa Hare Kṛṣṇa Kṛṣṇa Kṛṣṇa Hare Hare Hare Rama Hare Rama Rama Rama Hare Hare.
The Hare Krishna mantra is compose of Sanskrit names in the singular vocative case: Hare, Krishna, and Rama. This mantra is compose of two Sanskrit names of the Supreme Being, “Krishna” and “Rama.” “Hare” can be interpret as either the vocative form of Hari, another name of Vishnu meaning “he who removes illusion”. It is sometimes believe that “Rama” in “Hare Rama” means “Radharamana” or the beloved of Radha. The more common interpretation is that Rama refers to lord Rama of the Ramayana, an earlier avatar of Krishna.
A. C. Bhaktivedanta Swami describes the process of chanting the Maha Mantra as follows:
“Krishna consciousness is not an artificial imposition on the mind. This consciousness is the original energy of the living entity. When we hear the transcendental vibration, this consciousness is revived. This chanting of ‘Hare Krishna, Hare Krishna, Krishna Krishna, Hare Hare / Hare Rama, Hare Rama, Rama Rama, Hare Hare’ is directly enacted from the spiritual platform, and thus this sound vibration surpasses all lower strata of consciousness – namely sensual, mental, and intellectual. As such anyone can take part in the chanting without any previous qualification.”
“These sixteen names are destructive of the evil effects of Kali Yuga. No better means than this is to be seen in all the Vedas” told by Lord Brahma to Narada. The practice of chanting the Hare Krishna Maha mantra is recommend in the Puranas, the Pancharatra, and throughout Vaishnava literature in general. For example:
All the grievous sins are removed for one who worships Lord Hari, the Lord of all lords, and chants the holy name, the Maha-mantra.
— Padma Purana, 3.50.6
When the sixteen names and thirty-two syllables of the Hare Krishna mantra are loudly vibrated, Krishna dances on one’s tongue
— Stava-mala-vidyabhusana-bhasya, Baladeva Vidyabhushana in Bhaktisiddhanta’s Gaudiya Kanthahara 17:30
… [Anyone] can immediately become eligible to perform Vedic sacrifices if he once utters the holy name of the Supreme Personality of Godhead or chants about Him, hears about His pastimes, offers Him obeisances or even remembers Him.”
— Bhagavata Purana, 3:33 6
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