CC Ādi 13.66

tāṅra saṅge ānanda kare vaiṣṇavera gaṇa
kṛṣṇa-kathā, kṛṣṇa-pūjā, nāma-saṅkīrtana
Synonyms: 
tāṅra saṅge — with Him (Advaita Ācārya); ānanda — pleasure; kare — takes; vaiṣṇavera — of the devotees; gaṇa — assembly; kṛṣṇa-kathā — topics of Lord Kṛṣṇa; kṛṣṇa-pūjā — worship of Kṛṣṇa; nāma-saṅkīrtana — chanting of the Hare Kṛṣṇa mahā-mantra.
Translation: 
In the house of Advaita Ācārya, all the Vaiṣṇavas took pleasure in always talking of Kṛṣṇa, always worshiping Kṛṣṇa and always chanting the Hare Kṛṣṇa mahā-mantra.
Purport: 

On these principles only does the Kṛṣṇa consciousness movement go on. We have no business other than to talk of Kṛṣṇa, worship Kṛṣṇa and chant the Hare Kṛṣṇa mahā-mantra.