The chanting process is simple, sublime, and all-auspicious; even a child can take part
Frees one from sinful reaction and material bondage;
Chanting "Rama" gives the same result as chanting the 1000 names of Vishnu
Chanting once "Krishna" has the same potency as 3x the 1000 names of Vishnu
Also effective for someone who is not even aware of its potency
Contains the benefits of all other Vedic rites; to be chanting is the same as having performed all the Vedic processes of purification
The means in this age for attaining pure love of God (Krishna-prema)
Protects you from maya and falldowns (Bg 9.31p)
Purifies the whole atmosphere
Yields the same results as the processes of previous yugas
Elevates one even from a low background
The only possible process in this age: everything else is too difficult to execute (Bg 8.11p last para)
Chanters are most attractive to Krishna
All the Vedic knowledge is contained within the maha-mantra, the essence of the Vedas is to chant, and by chanting one realizes the meaning of the Vedas
The ultimate means to attain the ultimate success
Vedic verses glorifying the holy names
"By once chanting the holy name of the Lord, which consists of the two syllables ha-ri, one guarantees his path to liberation." (Skanda Purana)
"Simply by chanting one holy name of Hari, a sinful man can counteract the reactions to more sins than he is able to commit." (Brhad-Vishnu Purana)
"If one chants the holy name of the Lord, even in a helpless condition or without desiring to do so, all the reactions of his sinful life depart, just as when a lion roars, all the small animals flee in fear." (Garuda Purana)
Refer also to the story of Ajamila and the story of the Yavana
"Whatever result was obtained in Satya-yuga by meditating on Vishnu, in Treta-yuga by performing sacrifices, and in Dvapara-yuga by serving the Lord's lotus feet can be obtained in Kali-yuga simply by chanting the Hare Krishna maha-mantra." (SB 12.3.52)
"To say nothing of the spiritual advancement of persons who see the Supreme Person face to face, even a person born in a family of dog-eaters immediately becomes 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." (SB 3.33.6)
"My dear Narada, actually I do not reside in My abode, Vaikuntha, nor do I reside within the hearts of the yogis, but I reside in that place where My pure devotees chant My holy name and discuss My form, pastimes and qualities." (Padma Purana)
"O King, constant chanting of the holy name of the Lord after the ways of the great authorities is the doubtless and fearless way of success for all, including those who are free from all material desires, those who are desirous of all material enjoyment, and also those who are self-satisfied by dint of transcendental knowledge." (SB 2.1.11)
"Those who are actually advanced in knowledge are able to appreciate the essential value of this age of Kali. Such enlightened persons worship Kali-yuga because in this fallen age all perfection of life can easily be achieved by the performance of sankirtana." (SB 11.5.36)
"Living beings who are entangled in the complicated meshes of birth and death can be freed immediately by even unconsciously chanting the holy name of Krishna, which is feared by fear personified." (SB 1.1.14)