淨名經集解關中疏 2.263

2.263

喜見菩薩曰。色色空為二。色即是空非色滅空色性自空。如是受想行識識空為二。識即是空非識滅空識性自空。於其中通達者。是為入不二法門　色是礙。滅色是空二也。若悟色性自空。即空色不二。肇曰。若有不即空無不夷跡。餘陰准知。

The Bodhisattva Priyadarśana said, "Form and the emptiness of form constitute duality. Form is emptiness itself; it is not that the extinction of form is emptiness, but that the nature of form is inherently empty. In this way, feeling, perception, karmic formations, consciousness, and the emptiness of consciousness constitute duality. Consciousness is emptiness itself; it is not that the extinction of consciousness is emptiness, but that the nature of consciousness is inherently empty. To thoroughly penetrate this is entering the dharma gate of non-duality."
Form is obstruction; the extinction of form is emptiness—this is duality. If one realizes that the nature of form is inherently empty, then emptiness and form are non-dual. Sengzhao says, "If existence does not equal emptiness, non-existence cannot wipe out its traces. The remaining aggregates should be understood accordingly."