四分律刪繁補闕行事鈔 2.334

2.334

頰食者，令兩頰鼓起如獼猴狀也。不犯者：病、時欲過、難緣疾食者。

Stuffing the cheeks with food means puffing out both cheeks like a monkey. One does not commit an offense if: ill, the time is about to expire, or eating hastily due to perilous circumstances.