We should chant the name of the Lord, Hare Krishna, that has as much potency as the Lord Himself.
Srimad Bhagavatam 3.21.32
By chanting Krishna's Holy Name, one cleanses all the dust from the mirror of one's consciousness.
Chanting the holy name of the Lord immediately renovates the transcendental relationship of the living being with the Supreme Lord.
Sri Chaitanya Caritamrta,
Adi Lila, 7.76
Only the most intelligent people are entitled to engage in the process of chanting the mahamantra.
To associate with the holy name and chant the holy name is to associate with the Personality of Godhead directly.