Theravāda Vinaya
Mahāvibhaṅga
Sekhiyakaṇḍa
Ujjagghikavagga
Sekhiyā 14: Dutiyauccasaddasikkhāpada
Tena samayena buddho bhagavā sāvatthiyaṃ viharati jetavane anāthapiṇḍikassa ārāme. Tena kho pana samayena chabbaggiyā bhikkhū uccāsaddaṃ mahāsaddaṃ karontā antaraghare nisīdanti … pe ….
“Appasaddo antaraghare nisīdissāmīti sikkhā karaṇīyā”ti. (14:159)
Appasaddena antaraghare nisīditabbaṃ. Yo anādariyaṃ paṭicca uccāsaddaṃ mahāsaddaṃ karonto antaraghare nisīdati, āpatti dukkaṭassa.