四分律刪繁補闕行事鈔 2.434

2.434

言制意者。若不制境想，則犯罪浟漫；輕重不分，有無莫顯。故諸戒末，佛並具張；縱有缺文，但多是略耳。

Concerning the intention behind the formulation: If object ideation were not formulated, offenses would be vague and indefinite; gravity could not be distinguished, and presence or absence would not be clear. Therefore, at the end of each precept, the Buddha laid them out in full; even if the text has omissions, it is mostly just an abbreviation.