四分律比丘含注戒本 3.211

3.211

The Buddha was in Śrāvastī. A householder prepared an offering of food. The group of six made large mouthfuls so that their mouths could not receive them. The householder criticized them, saying: "Not knowing moderation, like pigs, dogs, camels, donkeys, oxen, and crows." The bhikṣus reported and brought up the matter, and the Buddha consequently formulated the precept.