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 composed of Sanskrit names in the singular vocative case: Hare, Krishna, and Rama. This mantra is composed of two Sanskrit names of the Supreme Being, "Krishna" and "Rama." "Hare" can be interpreted as either the vocative form of Hari, another name of Vishnu meaning "he who removes illusion". It is sometimes believed 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.
"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 mantra is recommended in the Puranas, the Pancharatra, and throughout Vaishnava literature in general. The mantra is repeated, either sung out loud (bhajan), congregationally (kirtan) or to oneself aloud or mentally (japa).
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