大般涅槃經義記 5.9

5.9

問曰：若彼是病行者，何故在於〈梵行品〉說？釋言：一品備論多法，諸經同有，不足可怪。又問：若彼兼論病行，何故偏名〈梵行品〉乎？此例亦多，如上〈如來性品〉中具明多法，題章偏名〈如來性品〉，此亦似彼，但經立品差別種種，或有從初、或復就後、或有據中、或復當相，非可一定。

Question: If that is illness practice, why is it spoken of in the 'Brahmacaryā Practice Chapter'? Answer: A single chapter fully discussing many dharmas is common to all sūtras, and is nothing to wonder at. Another question: If it also discusses illness practice, why is it exclusively named the 'Brahmacaryā Practice Chapter'? Examples of this are also numerous; just as the 'Tathāgata-Nature Chapter' above fully explains many dharmas, yet the chapter title is exclusively named 'Tathāgata-Nature Chapter', this is also similar to that. The establishment of chapters in sūtras has various differences: some take their name from the beginning, some from the end, some based on the middle, and some according to their predominant characteristic; it cannot be fixed.