There are many songs about the Lord's activities. For example, there is the Brahma-saṁhitā, sung by Lord Brahmā, Nārada-pañcarātra, sung by Nārada Muni, and Śrīmad-Bhāgavatam, sung by Śukadeva Gosvāmī. If these songs are heard by any person, he can easily get out of the clutches of material contamination. There should be no difficulty in hearing these songs of God. They are coming down from many, many millions of years ago, and people are still taking advantage of them. So why, at this time, should one not take full advantage and thus become liberated?
Glorifying the Lord's Transcendental Activities
In the First Canto, 5th Chapter, 22nd verse, of the Śrīmad-Bhāgavatam, Nārada Muni tells his disciple, Vyāsadeva, "My dear Vyāsa, you should know that persons who are engaged in executing austerities and penances, studying the Vedas, performing big sacrifices, chanting the hymns of the Vedas, speculating on transcendental knowledge and performing charitable functions have for all their auspicious activities simply to gain a place in the association of devotees and to chant the glories of the Lord." It is indicated here that chanting and glorifying the Lord is the ultimate activity of the living entity.
When a mantra or hymn is chanted softly and slowly, that is called japa. The same mantra, when chanted loudly, is called kīrtana. For example, the mahā-mantra (Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare) when uttered very softly only for one's own hearing is called japa. The same mantra, when chanted loudly for being heard by all others, is called kīrtana. The mahā-mantra can be used for japa and kīrtana also. When japa is practiced it is for the personal benefit of the chanter, but when kīrtana is performed it is for the benefit of all others who may hear.
In the Padma Purāṇa there is a statement: "For any person who is chanting the holy name either softly or loudly, the paths to liberation and even heavenly happiness are at once open."