Puranic literature, including verses Gaudiya tradition draws from the Brihannaradiya Purana and the Bhagavata Purana, teaches that each of the four ages, yugas, has its own prescribed dharma suited to the capacities of the people living in it, so that a practice fitting for an earlier and more spiritually capable age need not be the most effective one now.
Chaitanya, beginning in Navadvipa in Bengal in the early sixteenth century and continuing through his years in Puri, taught that for Kali Yuga, the current and most degraded of the four ages, the sacrifices and disciplines of earlier eras are largely impractical or ineffective, and that the congregational chanting of Krishna's names, sankirtana, performed aloud and in the company of others rather than silently or alone, is both the easiest and the most complete path available. The claim is doctrinal rather than merely devotional: sankirtana is presented as sufficient in itself, requiring no separate qualification of caste, learning or ritual purity, which is part of what made it spread so quickly through Bengal's towns and villages. Chaitanya himself led processions of chanters through the streets, and biographical and hagiographical accounts describe him falling into states of ecstatic absorption during these sessions, treated by his followers as confirmation that the practice itself carried the theological weight his teaching gave it, rather than functioning only as a preparatory devotion.