維摩經玄疏 6.52

6.52

一、明三藏教四門，即為四：一，有門；二，空門；三，有空門；四，非有非空門。

First, clarifying the four gates of the Tripiṭaka teaching, which constitute four: first, the gate of existence; second, the gate of emptiness; third, the gate of both existence and emptiness; fourth, the gate of neither existence nor emptiness.