成唯識論述記 3.497

3.497

述曰：此識既是果報之主，為善、染法之所依止，既恒是善，應不為惡依；是惡，亦應不為善依，互相違故，何得與二俱作所依？

The Commentary states: Since this consciousness is the master of retribution, serving as the support for wholesome and defiled phenomena, if it were constantly wholesome, it should not serve as a support for the unwholesome; if it were unwholesome, it should also not serve as a support for the wholesome. Because they mutually conflict, how could it serve as a support for both?