Remembrance of Krishna is not possible for the impure soul who has not practiced Krishna consciousness in devotional service. Therefore, one should practice Krishna consciousness from the very beginning of life. If one wants to achieve success at the end of his life, the process of remembering Krishna is essential. Therefore, one should constantly and incessantly chant the Hare Krishna Maha Mantra.
By performing congregational chanting of Hare Krishna mantra, one can destroy the sinful condition of material existence, purify the unclean heart and awaken all varieties of devotional service.
Everything that can be achieved by fruitive activities, penance, knowledge, detachment, mystic yoga, charity, religious duties and all other means of perfecting life is easily achieved by My devotee through loving service unto Me. If somehow or other My devotee desires promotion to heaven, liberation, or residence in My abode, he easily achieves such benedictions.
The wild tigers, elephants, bear and deer all together accompanied the Lord, and the Lord accompanied them in sankirtana. By this He proved that by the propagation of the sankirtana movement (congregational chanting and glorifying of the name of the Lord) even the wild animals can live in peace and friendship, and what to speak of men who are supposed to be civilized.
Srimad Bhagavatam Introduction.
Men become strong and stout by eating sufficient grains, but the devotee who simply eats ordinary grains but does not taste the transcendental pastimes of Lord Chaitanya Mahaprabhu and Krishna gradually becomes weak and falls down from the transcendental position.
Animalistic envy exists in human society as long as there is no performance of sankirtana-yajna.
Purport on Srimad Bhagavatam on 4.30.35