CC Antya 7.11

kali-kālera dharma — kṛṣṇa-nāma-saṅkīrtana
kṛṣṇa-śakti vinā nahe tāra pravartana
Synonyms: 
kali-kālera — of this age of Kali; dharma — the duty; kṛṣṇa-nāma-saṅkīrtana — chanting the holy name of Lord Kṛṣṇa; kṛṣṇa-śakti vinā — without being empowered by Lord Kṛṣṇa; nahe — is not; tāra — of that; pravartana — propagation.
Translation: 
“The fundamental religious system in the Age of Kali is the chanting of the holy name of Kṛṣṇa. Unless empowered by Kṛṣṇa, one cannot propagate the saṅkīrtana movement.