Srimad Bhagavatam [6.2.14 ]
stobhaṁ helanam eva vā
vaikuṇṭha-nāma-grahaṇam
aśeṣāgha-haraṁ viduḥ
One who chants the holy name of the Lord is immediately freed from the reactions of unlimited sins, even if he chants indirectly [to indicate something else], jokingly, for musical entertainment, or even neglectfully. This is accepted by all the learned scholars of the scriptures.
“Nama-sankirtana destroys all sins.”
Mahaprabhu said, “Nama-sankirtana is the best bhakti practice
Mahaprabhu said, “Krishna nama sankirtana is the dharma for the age of Kali."
nirantara kara kṛṣṇa-nāma-saṅkīrtana
Mahaprabhu said, “Serve Sri Krishna and the Vaisnavas and constantly chant Krishna Nama-sankirtana.”
vaiṣṇava-sevā, nāma-saṅkīrtana
dui kara, śīghra pābe śrī-kṛṣṇa-caraṇa
Mahaprabhu said, “By serving Vaisnavas and doing Nama-sankirtana, you will very quickly attain the lotus feet of Bhagavan Sri Krishna.
Chaitanya Charitamrita [2. 25.153-154]
bhāgavata karaha vicāra, pābe sūtra-śrutira artha-sāra
nirantara kara kṛṣṇa-nāma-saṅkīrtana, helāya mukti pābe prema-dhana
Sri Caitanya Mahaprabhu said, “By studying the Srimad Bhagavatam you will understand the essence of Sruti and Vedanta Sutra. And by constantly chanting Krishna Nama-sankirtana, you will attain liberation and the wealth of Krishna prema!
nava vidhi bhakti sarva-śreṣṭha nāma-saṅkīrtana
niraparādhe nāma laile pāya prema-dhana
Mahaprabhu said, “Nama-sankirtana is the best form of sadhana bhakti. Chanting without offense gives the treasure of Krishna prema.
Chaitanya Charitamrita [3.20.11]
nāma-saṅkīrtana haite sarvānartha-nāśa
sarva-śubhodaya, kṛṣṇa-premera ullāsa
“Nama-sankirtana destroys all anarthas, brings the rising of all good fortune, and thrills one with Krishna prema.
saṅkīrtana haite pāpa-saṁsāra-nāśana
citta-śuddhi, sarva-bhakti-sādhana-udgama
Mahaprabhu cried, “Hari Nama-sankirtana destroys sins and samsara. It cleanses the heart and manifests all types of bhakti sadhana.”
kṛṣṇa-premodgama, premāmṛta-āsvādana
kṛṣṇa-prāpti, sevāmṛta-samudre majjana
“By Nama-sankirtana, Krishna prema will appear in the heart. One will taste the nectar of Krishna’s love; attain Krishna, and submerge in the nectar ocean of Krishna’s eternal seva.
khāite śuite yathā tathā nāma laya
kāla-deśa-niyama nāhi, sarva siddhi haya
Sri Gauranga said, “For chanting Krishna nama there are no rules regarding time and place. If one chants Krishna nama even while eating or sleeping, one will attain all perfection i.e. Radha-Krishna nitya prema seva in the kunjas of Vrndavana.”
hare rama hare rama rama rama hare hare
iti sodasakam namnam kali-kalmasa-nasanam
natah parataropayah sarva-vedesu drsyate
The sixteen names of the Hare Krishna maha-mantra: hare krishna hare krishna krishna krishna hare hare, hare rama hare rama rama rama hare hare destroy all the inauspiciousness of the age of Kali. This is the conclusion of all the Vedas.
Brahmanda Purana [6.59-6]
hare krishna hare krishna krishna krishna hare hare
hare rama hare rama rama rama hare hare