首楞嚴義疏注經 8.171

8.171

依真起用，用不離體，體即真如。無漏清淨一真法界，此法界體本具如是無方妙用，故云本然。以即體故，名為真實。此之十行皆是證真菩薩自利、利他無礙自在圓融妙行，一一皆破微細無明，顯佛智德，漸漸圓滿。有此十番智斷功用，念念與薩婆若相應。《華嚴》云「此菩薩行與法界虛空等，以用諸佛不思議妙行故。」故此十行圓融無礙，即一論十、十不離一，故此最後即云一一皆是清淨真如性本然故。

Relying on the true, he gives rise to functioning; functioning does not depart from the essence, and the essence is precisely tathatā. It is the unpolluted, pure, one true dharmadhātu. The essence of this dharmadhātu fundamentally possesses such boundless wondrous functions; hence it says 'fundamentally so.' Because it is identical to the essence, it is called 'true reality.' These ten practices are all the wondrous, unimpeded, sovereign, and perfectly interfused practices of self-benefit and benefiting others belonging to the bodhisattva who realizes reality. Each and every one breaks through subtle avidyā, revealing the Buddha's wisdom and virtue, which gradually become fully rounded. Possessing this tenfold functioning of wisdom and elimination, he accords with sarvajñā from moment to moment. The Avataṃsaka says: 'The practices of this bodhisattva are equal to the dharmadhātu and empty space, because he employs the inconceivable wondrous practices of all Buddhas.' Therefore, these ten practices are perfectly interfused and unobstructed: discussing ten within one, the ten do not depart from the one; hence this last one states that each and every one is pure tathatā whose nature is fundamentally so.