首楞嚴義疏注經 8.260

8.260

從真起應，返入生死，從果入因之始，故云如來逆流。果法聖智，即法流也。從因入果，從生死入涅槃，故名順行而至。至，極也。起應之始，行因之極，順逆交際只一剎那，故云覺際入交。此即解脫道前無間道也，只於此處立為等覺。《華嚴》不說，含在第十地中，故彼地中便明受職是等覺也。《唯識》但破十一種障，亦此意也。今此別出，意在圓融之中備顯行布耳。

Arising from reality into responsive manifestation, returning to enter saṃsāra, is the beginning of entering cause from fruition; hence it is said, 'The Tathāgata flows against the current.' The sacred cognition of the fruition Dharma is the flow of the Dharma. Entering fruition from cause, entering nirvāṇa from saṃsāra, is named 'advancing with the current to arrive here'. 'Arrive' means reaching the utmost. The beginning of manifesting response and the culmination of practicing the cause intersect in a single kṣaṇa; hence it is said, 'Where the boundaries of enlightenment meet and intersect.' This is precisely the uninterrupted path prior to the path of liberation; right at this point, Equal Enlightenment is established. The Avataṃsaka does not speak of it separately, as it is subsumed within the tenth ground; therefore, on that ground it directly explains that receiving the office is Equal Enlightenment. The Vijñaptimātra's severing of only eleven kinds of hindrances also shares this intent. Now, bringing this out separately here is intended to fully display the sequential layout within complete interpenetration.