eta kahi' sandhya-kale cale gauraraya
kirtanera kaila prabhu tina sampradaya
eta kahi'-saying this; sandhya-kale—in the evening; cale—went out; gaura-raya—Gaurasundara; kirtanera—of performing sankirtana; kaila—made; prabhu—the Lord; tina—three; sampradaya—parties.
In the evening Lord Gaurasundara went out and formed three parties to perform kirtana.
This is a scheme for performing kirtana in a procession. During Sri Caitanya Mahaprabhu's time, one party was composed of twenty-one men: four people playing mrdangas, one leading the chanting, and sixteen others striking karatalas, responding to the leading chanter. If many men join the sankirtana movement, they may follow in the footsteps of Sri Caitanya Mahaprabhu and form different parties according to the time and the number of men available.
Link to this page: https://prabhupadabooks.com/cc/adi/17/135