Sri Chaitanya Mahaprabhu, in the first verse of Shikshashtaka, has glorified the chanting of the Holy Name `Sri Krishna'. `Sri' means beauty. What is the beauty of Krishna? Beauty is a potency attribute of Krishna. The main attribute of a thing is its beauty. That complete potency of Krishna in concrete form is called aradhika or briefly, Radhika. Sri Krishna is the predominating aspect of the moiety. As such Sri Krishna means Radha-Krishna. You are to chant the Holy Name Radha-Krishna. Knowing the significance of the Mahamantra, by chanting Hare Krishna Hare Krishna Krishna Krishna Hare Hare, Hare Rama Hare Rama Rama Rama Hare Hare, you can get sevenfold principal attainments. First attainment is ceto dharpana mārjanam, cleansing of the mind which is compared with a dusty mirror. Sankirtan means to chant correctly and completely. There are three meanings of Sankirtan :

(1) to chant the Holy Name without tenfold offences
(2) to chant completely the Name, Form, Attributes, Associates and Pastimes
(3) to chant loudly and collectively the Holy Name in the association of Shudha bhaktas.

Narada Goswami has been uttering the same Krishna-nam since time immemorial. But still, he cannot completely taste Krishna-nam. While speaking of the glories of Krishna-kirtan and utterance of the Names of Sri Sri Radha-Krishna, Chaitanya Mahaprabhu has said in Shikshashtakam, prati-padam purnamrtasvadanam. At every step in the utterance of the Name, complete transcendental ambrosia is tasted. It can never become stale. As God is Transcendental, a worshipper of God is also transcendental. As God is infinite, a worshipper of God, Vaishnava, is also infinite and their qualities are also infinite. If anybody says he has finished narrating the qualities, and those qualities will become stale, then he has not understood anything. Chaitanya Mahaprabhu heard about the lives of Dhruva and Prahlada from Gadadhar Pandit Goswami repeatedly for one hundred times. But we have not heard even once, the full biographies of Dhruva and Prahlad. We say that we have already heard, please tell us something new. Chaitanya Mahaprabhu after hearing one hundred times wanted to hear again from Gadadhar Pandit Goswami. If after hearing the glories of the Lord and His associates, we have the desire to hear again, then we have entered into the devotional spiritual realm. Otherwise, you are outside the devotional spiritual realm and have learned nothing about spiritual life. If you want to perform bhajan, you are to understand this - the difference between transcendental sound and material sound.