After the first Rains Retreat (Vassa) at the Deer Park at Sarnath, the Buddha went to Rajagaha city where 1250 Arahats,(Enlightened saints) who were the Buddha's disciples, without prior appointment, returned from their wanderings to pay respect to the Buddha. They assembled in the Veruvana Monastery with the two chief disciples of the Buddha, Ven. Sariputta and Ven. Moggalana.
The assembly is called the Fourfold Assembly because it consisted of four factors:
- All 1250 were Arahats
- All of them were ordained by the Buddha himself
- They assembled by themselves without any prior call
- It was the full moon day of Magha month