四分律刪繁補闕行事鈔 2.322

2.322

羹飯等食者，非飯至羹盡，羹至飯盡也。不犯者：有病、若正須飯、正須羹、日時欲過、二難疾食者。

Eating soup and rice equally means not eating rice until the soup is finished, nor eating soup until the rice is finished. One does not commit an offense if: having an illness, strictly needing rice, strictly needing soup, the time of day being about to expire, or eating hastily due to the two perils.