The holy name of Krishna is so attractive that anyone who chants it — including all living entities, moving and nonmoving, and even Lord Krishna Himself — becomes imbued with love of Krishna. This is the effect of chanting the Hare Krishna maha-mantra.
Chaitanya Caritamrta, Antya Lila 3.268,
The holy name of the Lord should be chanted twenty-four hours daily.
Srimad Bhagavatam 4.24.70,
This process of chanting is the best process of self-realization in this age; therefore Lord Caitanya preached it so nicely for the benefit of all humanity.
Srimad Bhagavatam 3.24.35,
The chanting itself purifies us and as the heart becomes purified, the Holy name is revealed to us as being non-different than Lord Krishna.
Devotional service begins with the chanting of the Hare Krishna mantra and side by side trying to understand Krishna in truth.
Bhagavad Gita 9.20,
One can attain salvation simply by chanting the holy name of the Lord.
Srimad Bhagavatam 1.18.7