四分律比丘含注戒本 2.153

2.153

(The Buddha was in Śrāvastī. Bhikṣus were staying on the upper story of a building. [One] sat on a couch with loose legs, and a leg detached and fell onto a bhikṣu [below], injuring his body and making him bleed. Turning his face upward, he angrily reviled [him]. The bhikṣus raised the offense, and the Buddha rebuked [the monk] and formulated [the precept].)