起信論疏筆削記 8.42

8.42

此真下，二、束四義成二門。初義即真中不變，妄中體空，由此二義成真如門。此門攝妄則妄體空，攝真則真不變，染淨平等，一相無相，故有此門。後義即真中隨緣，妄中成事，由此二義成生滅門。此門攝真則真隨緣，攝妄則妄成事，即成染淨諸法差別等相，故有此門。

"This truth...", etc., secondly, bundles the four meanings to form two gates. The first meanings are the unchanging within the true and the emptiness of essence within the deluded; through these two meanings the gate of tathatā is established. When this gate encompasses the deluded, the deluded is empty in essence; when it encompasses the true, the true is unchanging; defilement and purity are equal, of a single characteristic and characteristicless; hence this gate exists. The second meanings are according with conditions within the true and effecting phenomena within the deluded; through these two meanings the gate of arising and ceasing is established. When this gate encompasses the true, the true accords with conditions; when it encompasses the deluded, the deluded effects phenomena; that is, it constitutes the differentiated marks of all defiled and pure dharmas; hence this gate exists.