仁王經疏 3.161

3.161

Question: The four dhyānas and the formless realm also have pure dharmas; how can they be said to be impure? Solution: Impurity itself has many kinds. As stated in the twenty-sixth fascicle of the Yogācārabhūmi, there are six kinds of impurity: 1. Impurity of putrid filth, which itself has two kinds: (i) internal impurity, meaning hair, body hair, and so forth; (ii) external impurity, meaning blue-bruised corpses and so forth. 2. Impurity of suffering and affliction, meaning feelings born of painful contact. 3. Inferior impurity, namely the desire realm. 4. Correlative impurity: just as, when compared to the superior purity of the formless realm, the dharmas of the form realm seem impure; and when compared to the quiescence of nirvāṇa of the buddha-kāya, everything up to the peak of existence seems impure. 5. Impurity of afflictions, meaning all the fetters, torpors, and secondary afflictions throughout the three realms. 6. Impurity of destruction, meaning that the five appropriation aggregates are impermanent, non-eternal, unreliable, and of the nature of change and decay, as fully explained there. Because of this, both the dhyānas and the formless realm are called impure.