Preached at Sāvatthi on Komudī, the full-moon day of the fourth month. The monks had gathered together to see the Buddha and eminent disciples had been busy instructing their pupils in the various attainments. The Commentary says the Buddha had not gone on tour as usual because he wanted to give the monks opportunity of developing their attainments. (MA.ii.895-6.)
Seeing them thus assembled, the Buddha was pleased with their demeanour and described how in the confraternity of monks were to be found men of various degrees of attainment. Some of them practised the cultivation of mindfulness by breathing exercises and the Buddha proceeded to explain how it was done. Such mindfulness leads to the development of the four satipatthānas, and these, in turn, to the seven bojjhangas. Through them one attains deliverance through understanding. M.iii.78-88.