釋氏要覽 3.27

3.27

The Abhiniṣkramaṇa-sūtra says: “At that time, monks gathered in one hall, and two monks expounded the Dharma, which led to mutual interference. They then built two halls, but because they were close together, they enticed each other and mingled back and forth, disrupting the assembly. The Buddha laid down the rule: ‘From now on, [two expounders] must not share one hall, nor may two halls be close together; also, those in that hall may not come to this hall, nor may those in this hall go to that hall; they must not harbor hatred or disdain toward [each other's] Dharma gates’ (like the three trainings nowadays mutually criticizing one another).”