法界次第初門 1.88

1.88

次五陰而辨十二入者，以惑者迷色偏重故。大聖教門，開色為十、心但為二，合為十二也。通稱入者，入以涉入為義，根、塵相對則有識生，識依根、塵仍為能入，根、塵即是所入。今此十二從所入受名，故通受入名。內六入者，此之六法親故屬內，為識所依，故名為入。亦名根者，根以能生為義，此六既並有生識之功，故通名根也。

Next to the five skandhas, we elucidate the twelve āyatanas because deluded persons are predominantly confused about form. In the great sages' teaching gates, opening form yields ten, while mind is merely two, combining to make twelve. They are universally called "āyatanas" (ru) because ru has the meaning of "entering into and interacting": when sense faculties and sense objects face each other, consciousness arises; relying on faculties and objects, consciousness functions as that which enters, while faculties and objects are that which is entered. Now, these twelve receive their name from that which is entered; hence they universally receive the name "āyatana." The six internal āyatanas: these six dharmas, being intimate, belong to the internal, and serve as that upon which consciousness relies; hence they are named āyatanas. They are also named "faculties" (indriya) because indriya has the meaning of "being able to produce"; since these six all possess the efficacy of producing consciousness, they are universally named faculties.