法界次第初門 2.203

2.203

次三解脫門而辯三無漏根者，解脫既是涅槃之門，若善修三解脫，必定發真無漏，證有餘涅槃。得有餘涅槃自有三道不同，謂見道、修道、無學道也。證三道時必發三根，故次三解脫而辯之。通名根者，根以住立、能生為義。得此三法，住立不退，生真智照，故名根也。

The three untainted faculties are explained next after the three gates of liberation because liberation is indeed the gate to nirvāṇa. If one skillfully cultivates the three liberations, one will unfailingly produce genuine untaintedness and realize nirvāṇa with remainder. Attaining nirvāṇa with remainder naturally has three different paths: namely, the path of seeing, the path of cultivation, and the path of the adept (aśaikṣa). When realizing these three paths, one unfailingly gives rise to the three faculties; therefore, they are explained next after the three liberations. They are collectively called 'faculties' (indriya) because a faculty has the meanings of 'standing firm' and 'being able to generate.' Having attained these three dharmas, one stands firm without retrogressing and generates the illumination of genuine wisdom; hence they are called 'faculties.'