大般涅槃經集解 24.40

24.40

案僧亮曰：次答云何諸菩薩而得不壞眾也。因上聲聞護法莊嚴眷屬，眷屬是佛外果，即以外果勸進也。

Sengliang comments: Next is the answer to: 'How do the bodhisattvas obtain an indestructible community?' Because of the śrāvakas' protection of the Dharma adorning their retinue above, and the retinue being the Buddha's external fruit, he immediately uses the external fruit to exhort and advance them.