On the first day of the Rain Retreat period, the Bhikkhus assembled in Rjagaha and determined the cave called Sattapanna, by the side Mount Vebhra, as the meeting place for the purpose. During this time and from the fullmoon day of the Svana month onwards, Venerable nanda was steadily and devotedly accelerating his efforts, never being negligent or heedless of what was required of him. Nevertheless, success seemed always to elude him until the day of the General Meeting. Exhausted and somewhat discouraged, he reclined, hoping to lie down for a rest. It was miraculously at this moment, while the upper part of his body was in a slanting position, not yet touching the floor, that he was enlightened into Arahatship. Such being the case, he was unique in that it cannot be said in exactly what posture of the body he became an Arahant. This was the fulfilment of the condition set down for the General Meeting, which was convened, as earlier stipulated, by 500 Arahants.

The assembled Bhikkhus agreed to have Venerable Mahkassapa chair the meeting, with Venerable Upli to expound the Vinaya or the disciplinary rules, and Venerable nanda to be assigned the Stta or Discourses and the Abhidhamma. This was the first of its kind in Buddhism. It lasted seven months and was throughout the period under the patronage of King Ajtasattu. This has become ever since the source of reference as far as the Buddha's Dispensation (i.e. the Norm and the Law) are concerned. It had been transmitted orally by words of mouths for some centuries before attempts were made to have it written.