俱舍論疏 1.19

1.19

一、釋品名者，性義、族義、持義名界。別義、類義、分義名品。此品多門，分別界故，由此故名〈分別界品〉。所以多門分別界者，蘊唯有為，處唯根境，界中具顯六根境識。若具依三門明有見等，文多繁廣。若分別蘊處，類釋於界，義即難知；若以有見就界分別，類釋蘊、處，義即易解，故就界門分別有見等。第者，居也。一者，初也。此品居初，故云「第一」。

First, regarding the explanation of the chapter title: Nature, lineage, and maintaining are what is meant by 'dhātu' (element). Distinction, class, and division are what is meant by 'chapter'. Because this chapter analyzes the dhātus through many approaches, it is therefore named the 'Chapter: Exposition of the Dhātus'. Why are the dhātus analyzed through many approaches? The skandhas are exclusively conditioned, the āyatanas are exclusively faculties and objects, whereas within the dhātus the six faculties, objects, and consciousnesses are fully manifested. If one were to explain visible [phenomena] and so forth comprehensively according to all three approaches, the text would be exceedingly voluminous. If one analyzed the skandhas and āyatanas to analogously explain the dhātus, the meaning would be difficult to understand; but if one uses visible [phenomena] to analyze the dhātus and analogously explains the skandhas and āyatanas, the meaning will be easily comprehended. Therefore, visible [phenomena] and so forth are analyzed by way of the dhātus. 'Di' (rank) means to reside. 'Yi' (one) means the beginning. Because this chapter resides at the beginning, it is called 'First'.