Cc Adi 13.66

In the house of Advaita Acarya, all the Vaisnavas took pleasure in always talking of Krsna, always worshiping Krsna and always chanting the Hare Krsna maha-mantra.

Srila Prabhupada’s purport:

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