大般涅槃經義記 8.122

8.122

下翻一、二是凡相中，「若言一、二是凡夫相」牒其難辭，「是乃十住非凡夫相」翻其難辭。「何以」下釋，先徵後解，於中先出一、二法體，「一謂涅槃，二謂生死」。次釋其義，涅槃體常，不變故一。生死無常，「愛、無明」等前後分異，是故言二，皆初徵問，後釋可知。

Below, in overturning [the claim that] the one and the two are marks of ordinary beings, "If one says that the one and the two are marks of ordinary beings" takes up the words of his objection; "these are [marks of] the ten abodes and not marks of ordinary beings" overturns the words of his objection. The explanation from "Why is this?" onward first poses a pressing question and then explains it, wherein it first identifies the essences of the dharmas of the one and the two: "The one refers to nirvāṇa; the two refers to saṃsāra." Next it explains their meaning: the essence of nirvāṇa is permanent; because it is unchanging, it is one. Saṃsāra is impermanent; "craving, ignorance," and so forth differ before and after, and are therefore said to be two. In all cases, first there is a pressing question, and the subsequent explanation may be understood.