四分律比丘含注戒本 2.692

2.692

佛在舍衛。多比丘集，論法毘尼。六群相謂「看諸比丘，似為我等作羯磨」，從座起去。比丘喚住而故去。以事白佛，便訶而制戒。

The Buddha was in Śrāvastī. Many bhikṣus assembled to discuss the Dharma and Vinaya. The group-of-six said to one another, "Look at those bhikṣus; it seems they are going to perform a karman against us," and rose from their seats and left. The bhikṣus called them to stay, but they left intentionally. They informed the Buddha of the matter, who rebuked them and instituted the rule.