大般涅槃經集解 30.44

30.44

案僧亮曰：以輕重因緣也。苦樂性不相離者，三苦不相離也。寶亮曰：實以無三惡苦，故有實樂。苦樂性不相離者，十住無漏之解，從初住至金剛心以來當分除惑，於無惑邊恒是實樂。而無漏之體未免世諦，故舉體是苦，故言苦樂性不相離也。

Sengliang comments: This is due to the causal conditions of lightness and heaviness. That the natures of suffering and pleasure are not separate from each other means that the three sufferings are not separate from each other. Baoliang comments: It is truly because of the absence of the suffering of the three evil destinies that there is actual pleasure. That the natures of suffering and pleasure are not separate means: the unoutflowing understanding of the ten abodes, from the first abode up to the vajropama-citta, eliminates delusions according to its portion; with respect to the aspect without delusion, it is constantly actual pleasure. Yet, because the substance of the unoutflowing has not yet escaped the conventional truth, in its entirety it is suffering. Therefore, it is said that the natures of suffering and pleasure are not separate from each other.