大乘起信論裂網疏 2.7

2.7

一心，即指眾生現前介爾心也。言二種門者，非是前後左右名為二也。秖是隨緣不變，即此生滅心名真如門；不變隨緣，即此真如心名生滅門。正所謂是舍唯有一門，亦所謂十方薄伽梵一路涅槃門。但迷之則生死始，則真如舉體而為生滅；悟之則輪迴息，則生滅當體便是真如。故約迷、悟而明二種門也。又對迷說悟即生滅門，迷悟平等乃真如門。言此二門各攝一切法者，謂約真如門則攝百界千如、五位百法，一一無非真如，性恒平等、無增無減，無別異故。約生滅門，亦攝百界千如、五位百法，一一無非生滅，以六凡諸法是迷染因緣所成；四聖諸法是悟淨因緣所成。世、出世間無有一法不從生滅因緣而顯示故。言以此展轉不相離者，謂離一心真如則無生滅可得，如離於方別無迷悟，亦如離於濕性別無氷水；離一心生滅亦無真如可得，如離迷悟別無有方，亦如離於氷水別無濕性也。

'One mind' refers precisely to the momentary mind present right before sentient beings. Speaking of 'two aspects' does not mean that front and back or left and right are called two. It is merely that according with conditions yet immutable, this very arising-and-ceasing mind is called the aspect of tathatā; immutable yet according with conditions, this very mind of tathatā is called the aspect of arising and ceasing. It is precisely what is called 'this house has only one gate', and also what is called 'the one single path of the nirvāṇa gate of the Bhagavats of the ten directions'. But when one is deluded about it, saṃsāra begins, and tathatā in its entire essence becomes arising and ceasing; when one awakens to it, transmigration ceases, and arising and ceasing in its very essence is precisely tathatā. Therefore, the two aspects are clarified in terms of delusion and awakening. Moreover, speaking of awakening in contrast to delusion is the aspect of arising and ceasing; the equality of delusion and awakening is the aspect of tathatā. Saying that 'these two aspects each encompass all dharmas' means that in terms of the aspect of tathatā, it encompasses the hundred realms and thousand thusnesses and the hundred dharmas of the five categories, each and every one being nothing other than tathatā, because its nature is eternally equal, neither increasing nor decreasing, and without distinction. In terms of the aspect of arising and ceasing, it also encompasses the hundred realms and thousand thusnesses and the hundred dharmas of the five categories, each and every one being nothing other than arising and ceasing, because the dharmas of the six ordinary realms are formed by the causes and conditions of delusion and defilement, and the dharmas of the four noble realms are formed by the causes and conditions of awakening and purity. Throughout the worldly and the world-transcending, there is not a single dharma that is not revealed through the causes and conditions of arising and ceasing. Saying 'because they are mutually inseparable' means that apart from the one mind of tathatā, there is no arising and ceasing to be found, just as apart from direction there is no delusion or awakening, and just as apart from the wet nature there is no ice or water; apart from the one mind of arising and ceasing, there is also no tathatā to be found, just as apart from delusion and awakening there is no direction, and just as apart from ice and water there is no wet nature.