淨名經集解關中疏 2.269

2.269

心無礙菩薩大。身身滅為二。身即是身滅。所以者何。見身實相者不起見身及以滅身。身與滅身無二無分別。於其中不驚不懼者。是為入不二法門　陰苦聚為身患苦。故滅身為二。若悟陰假會即身非身無生無滅。名見實相為不二也。

The Bodhisattva Apratihatacitta said, "The body and the extinction of the body constitute duality. The body is itself the extinction of the body. Why is this? One who sees the true mark of the body does not give rise to the view of the body or the extinction of the body. The body and the extinction of the body are non-dual and without discrimination. Being neither startled nor terrified within this is entering the dharma gate of non-duality."
The aggregates, as a collection of suffering, are the body; suffering from affliction and thus destroying the body constitutes duality. If one realizes that the aggregates are a provisional convergence, then the body is not a body, devoid of arising and extinction; this is called seeing the true mark and being non-dual.