四分戒本疏卷第一．第二．第三 3.45

3.45

說法至日暮戒第二十二　制意者。凡男女有別。居不同處。僧眾舉動須避識涉。生人信敬。日沒群聚致外情疑。容自壞行。過損不輕。故聖以制　別緣有六。一是僧甄去不差。二集尼眾。三教授說法。四日暮。五日暮想。六說法不止便犯。已下正明戒本。此戒因差難陀教授尼。至日暮不蘭本寺。為俗所譏。佛便制戒。

Precept 22: Preaching the Dharma until Sunset / Regarding the intention behind establishing [this precept]: In general, men and women are distinct and should not dwell in the same place. The movements of the saṅgha must avoid suspicion and contact so as to engender people's faith and reverence. Gathering in groups after sunset leads to suspicion from the outside and allows one's own practice to be corrupted; the fault and harm are not light, which is why the Sage established [this precept]. / There are six specific conditions: first, being selected and deputed by the saṅgha; second, the assembly of nuns being gathered; third, instructing and preaching the Dharma; fourth, sunset; fifth, the perception of sunset; sixth, continuing to preach without stopping, whereupon one commits the offense. Below, the text of the precept is properly explained. This precept arose because Nanda was deputed to instruct the nuns; when sunset came, he had not returned to his own monastery, which drew criticism from the laity. The Buddha thereupon established the precept.