“In the sastra it is said this Kali-yuga is full of faults, so many faults. It is the ocean of faults. But there is a very nice thing, asti hy eko mahan gunah, a very great quality. What is that? Kirtanad eva krsnasya mukta-sangah param vrajet [SB 12.3.51]. If you simply chant Hare Krishna mantra, then you become perfect. Is it very difficult? Chant Hare Krishna and you become perfect. But we are so unfortunate, we are not even prepared to chant. This is our position. So you have to make little determination that ‘I shall chant henceforward Hare Krishna mantra.’ Then everything is all right.” (Srila Prabhupada from Lecture)
and this from Srimad Bhagavatam 8.5.23
When Kṛṣṇa appeared, He gave His orders, and when Kṛṣṇa Himself appeared as a devotee, as Śrī Caitanya Mahāprabhu, He showed us the path by which to cross the ocean of Kali-yuga. That is the path of The Hare Kṛṣṇa Movement. When Śrī Caitanya Mahāprabhu appeared, He ushered in the era for the saṅkīrtana movement. It is also said that for ten thousand years this era will continue. This means that simply by accepting the saṅkīrtana movement and chanting the Hare Kṛṣṇa mahā-mantra, the fallen souls of this Kali-yuga will be delivered. After the Battle of Kurukṣetra, at which Bhagavad-gītā was spoken, Kali-yuga continues for 432,000 years, of which only 5,000 years have passed. Thus there is still a balance of 427,000 years to come. Of these 427,000 years, the 10,000 years of the saṅkīrtana movement inaugurated by Śrī Caitanya Mahāprabhu 500 years ago provide the opportunity for the fallen souls of Kali-yuga to take to the Kṛṣṇa consciousness movement, chant the Hare Kṛṣṇa mahā-mantra and thus be delivered from the clutches of material existence and return home, back to Godhead.
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The Hare Krishna Movement 