四分律比丘含注戒本 2.45

2.45

佛在曠野城。六群比丘與諸長者講堂誦經，語聲高大，亂坐禪者。比丘舉過白佛，因制此戒。

The Buddha was in the city of Aṭavī. The group of six bhikṣus recited sūtras together with various householders in a lecture hall; their voices were loud and disturbed those who were meditating. Bhikṣus brought up the fault and reported it to the Buddha, who on this account formulated this precept.