'Hearing & Chanting are the basic principles'

the basic yet most sacred hymn in Hinduism.

The whole process of spiritual culture is aimed at changing the heart of the living being in the matter of his eternal relation with the Supreme Lord as subordinate servant, which is his eternal constitutional position. So with the progress of devotional service, the reaction of change in the heart is exhibited by gradual detachment from the sense of material enjoyment by a false sense of lording it over the world and an increase in the attitude of rendering loving service to the Lord. It is expected by all means that by discharging regulated devotional service one must manifest the change of heart. If there is no such change, the heart must be considered steel-framed, for it is not melted even when there is chanting of the holy name of the Lord. We must always remember that hearing and chanting are the basic principles of discharging devotional duties.

The devotee who chants the holy name of the Lord in a perfectly offenseless manner and is friendly to everyone can actually relish the transcendental taste of glorifying the Lord. And the result of such realization is reflected in the cessation of all material desires.

Srila Prabhupada purport (SB 2.3.24)