四分比丘戒本疏 1.22

1.22

述曰：結已審持也。謂將欲說正宗諸戒，先且總審眾有淨穢。穢者聽戒律教所遮，知遮而聽犯序三問。又隨隱罪𨒬三問時，復犯正篇三問之默。故今審之，令不隱也。故說戒犍度文云「若有犯者，不得說戒、不得聞戒。不得向有犯者懺悔，犯者不得受他懺悔。」既審已訖，眾同憶持，故云是事如是持。

The commentary states: This is concluding by investigating their observance. That is to say, being about to recite the main body of the various precepts, one first comprehensively investigates whether the assembly is pure or defiled. For a defiled person to listen to the precepts is prohibited by the Vinaya teachings; knowing that it is prohibited and yet listening violates the three inquiries of the prologue. Moreover, each time one conceals an offence and passes through the three inquiries, one further violates the silence of the three inquiries of the main divisions. Therefore, one now investigates so that they do not conceal it. Thus the Khandhaka on the Recitation of the Prātimokṣa states: "If one has committed an offence, one may not recite the precepts nor listen to the precepts. One may not confess to one who has committed an offence, and an offender may not receive another's confession." Having completed the investigation, the assembly remembers and upholds it alike; therefore it says, "Thus should it be held."