俱舍論疏 16.21

16.21

「論曰至名黑白業」，此師意：以地獄唯不善感故，順彼受業，名為純黑。欲界餘趣通二異熟故，順彼善、惡諸業，名雜業也。此二業以因從果，名黑、雜也。

"The Śāstra says: […] is called dark-and-bright karma"—the intention of this master is: because the hells are induced solely by the unwholesome, karma conducive to experiencing [fruit] there is called purely dark. Because the remaining destinies of the desire realm encompass both maturations, the wholesome and unwholesome karmas conducive to experiencing [fruit] in them are called mixed karma. These two karmas are named 'dark' and 'mixed' according to the fruit rather than the cause.