大般涅槃經義記 1.130

1.130

問曰：此經涅槃為宗，今以何故宣說菩提？釋言：分相，菩提、涅槃兩門各別；若據攝相，互得相成。今據攝相，故說菩薩亦成涅槃，亦可此經具明菩提涅槃常果。經初題言「大涅槃」者，名不盡法，且舉一邊，不具言耳。〈純陀章〉中，義二文三。言義二者，一明如來真身常住、二明如來應身無常。

Question: This sūtra takes nirvāṇa as its central doctrine; why does it now proclaim bodhi? Explanation: In terms of differentiated characteristics, the two approaches of bodhi and nirvāṇa are each distinct; if based on inclusive characteristics, they mutually accomplish each other. Here, based on inclusive characteristics, it is said that bodhi also accomplishes nirvāṇa; alternatively, this sūtra fully clarifies the eternal fruit of bodhi and nirvāṇa. That the title at the beginning of the sūtra says "Mahānirvāṇa" is because the name does not exhaust the dharma; it merely raises one aspect and does not state it fully. In the "Cunda Section," there are two meanings and three textual passages. Regarding the two meanings: first, clarifying that the Tathāgata's true body is eternally abiding; second, clarifying that the Tathāgata's response body is impermanent.