Now that the Buddha had sixty disciples, he directed them to disperse to spread the doctrine of the buddhas so that as many people as possible could benefit from it. He told them not to go in groups, but one by one, to calm the spirits of all people and teach them to overcome suffering. He himself planned to journey back to Uruvilva village in the land of Magadha to teach.
Once he had dispersed the sixty arhats, the Buddha left the Deer Park and headed southeast to Magadha and Uruvilva village and a hamlet, where there lived about a thousand men were worshipping fire and seeking enlightenment under the leadership of three brothers named Kashyapa (Kaśyapa). The most imposing of the three was Uruvilva Kashyapa, and he had over a hundred followers of his own. The other two were Nadi (Nadī) and Gaya (Gayā), and they too had followers. The Buddha intended to replace their delusions with enlightenment, but he three had a very high opinion of their level of consciousness and of their magical powers, and they were no more receptive to his message than we might imagine. Uruvilva Kashyapa even entertained the fantasy that he was already an arhat, and would be ready for buddhahood almost immediately.
The Buddha spoke to Uruvilva Kashyapa and worked a number of miracles —many say 3,500 of them— and Uruvilva Kashyapa was much humbled and asked to be a disciple. He cut off his long tangled ascetic’s hair and threw it in the river to show his transformation. So did all 500 of his followers. When Uruvilva Kashyapa’s two brothers saw what had happened, they too cut off their tangled and dirty hair and asked to be disciples, and their followers followed their example, just as Uruvilva Kashyapa’s disciples had.
And thus the three brothers and their thousand followers all understood the truth and joined the growing band of arhats.
Accompanied by them, the Buddha went on to the town of Rajagaha, further down the road but still in the land of Magadha, to fulfill his promise to King Bimbisara to tell him of his enlightenment and bring the truth to all the king’s people. He sent his arhats ahead into Rajagaha to spread the word, and himself headed for a palm grove, and there, his heart filled with compassion, he preached to King Bimbisara and the people of Rajagaha so that they would be able to avoid suffering.
People had begun to speak of that Buddha and his message as the “three treasures”: namely the Buddha himself and all the other buddhas past and future, the Buddhist teachings, which were called the “law” (dharma) because they are the way the world really works, and the Buddha’s committed followers who left their families to learn and teach. They were called the sangha (saṅgha), which meant “community” or “craft guild” or “religious order.”
King Bimbisara told the Buddha he wished to become a home-dwelling follower and to support the Three Treasures. and he presented him with a plot of ground called the Bamboo Forest Retreat (Veṇuvanta Vihāra). This became the first monastery, establishing the tradition of monasteries that continues today.