淨名經集解關中疏 2.249

2.249

不眴菩薩曰。受不受為二。若法不受則不可得。以不可得故無取無捨無作無行。是為入不二法門　凡夫受著五陰。無學不受。此為二也。肇曰。有心必有所受。有所受必有所不受。此為二也。若悟法本空二俱不受則無得無行為不二也。

The Bodhisattva Animisa said, "Apprehending and not apprehending constitute duality. If dharmas are not apprehended, they cannot be obtained; because they cannot be obtained, there is no grasping and no discarding, no activity and no practice. This is entering the dharma gate of non-duality."
Ordinary people apprehend and cling to the five aggregates; those beyond training do not apprehend [them]—this constitutes duality. Sengzhao says, "Where there is a mind, there must be that which is apprehended; where there is that which is apprehended, there must be that which is not apprehended. This constitutes duality. If one realizes that dharmas are originally empty, and apprehends neither of the two, then there is nothing obtained and no practice; this is non-duality."