大般涅槃經集解 56.84

56.84

案僧亮曰：第四難，性常不應有退也。寶亮曰：若有退不退者，是則退者無有佛性，豈是悉有耶？

Sengliang states: The fourth objection: if the nature is permanent, there ought not to be retrogression. Baoliang states: If there is retrogression and non-retrogression, then those who retrogress lack the buddhadhātu; how could it be that all possess it?