The essence of the instructions that Sriman Mahaprabhu imparted to Sri Sanatana Gosvami [or the essence of the eternal instruction of dharma] is that one should perform nama-saìkirtana in the association of saintly persons. The hare krsna maha-mantra is the Sri Radha-Krsna paraka-mantra, or the mantra that helps one attain Sri Radha-Krsna. One obtains prema for the Divine Couple, Sri Radha-Krsna, and direct realization of one’s eternal constitutional position (svarupa), by constantly practising the chanting of this maha-mantra.
 
 
Gaudiya Vedanta Publications