A fluent [monastic] reciter can recite the two Pāṭimokkhas without hindrance and perform every half month during the uposatha; he knows [what to do] on the six uposatha days and can preach the dharma for the patrons, if required to recite one or two Āgama collections, he knows [what to do] and there is no problem. 「反復流利者，誦二部波羅提木叉，無有滯礙，半月半月盡布薩；悉知六齋日，能爲人說法，若誦一阿含二阿含，亦知無礙」 (T 1462.24.782a19–22).

The cenobitical poṣadha (busa) consisted of a recitation of the monastic code (prātimokṣa) and a repentance ceremony. It normally occurred twice a month, on the days of the new moon and the full moon in the so-called 'poṣadha hall' (poṣadhāgāra).

The Abhidharmakośabhāṣya uses poṣadha to gloss over upavāsa in Abhidharmakośa 4.28 (see Pradhan 1975, 213–214; Abidamo jushelun 阿毘達磨倶舍論, T 1558.29.75b7–10). Vasubandhu 世親 splits the word poṣadha into poṣa ( 'nourishing' ) and √dhā ( 'give' ) and this quasi-etymological explanation, i.e., ( 'nourishment-giving' ), has the backing of other Indian Buddhist sources and is often reiterated by modern scholars. However, linguistically speaking, it seems unlikely, for poṣadha is a Prakrit noun derived from Skt. upavasathā, which in turn is derived from upa+√vas ( 'to dwell near [the gods]' ). Yijing 一行 provides yet another folk etymology by splitting poṣadha into √puṣ ( 'nourish' ) + √dhai ( 'cleanse' ) in one of his commentarial notes to the Mūlasarvâstivāda One Hundred and One Formal Acts 〔Baiyi jiemo 百一羯磨, T 1453.24.468b25〕 .