四分比丘戒本疏 2.41

2.41

Ninth: the precept against teaching the Dharma to a woman for more than five or six sentences in the absence of a discerning man. 'Five or six sentences' refers to five or six categories. For instance, the five aggregates are five categories, and the six sense-bases are six categories; explaining five or six categories extensively does not yet constitute an offence. If there is a discerning man alongside as a third party who distinguishes between purity and defilement, there is no limit on the amount. The sixth fascicle of the Sarvāstivāda-śāstra states that he must be a white-robed layman; if he is a monastic, he cannot [serve as the witness], because their circumstances are the same. If we follow this Vinaya, below, in the presence of valuables facing a husband, a fourth person is permitted, not facing [the husband] a third person is permitted, and for sitting in the open with a woman a third person is permitted. The texts of the Vinaya all say: 'If there are two monks as companions, it is not an offence.' Accordingly, this differs from the Sarvāstivāda-śāstra.