仁王護國般若波羅蜜多經疏 2.32

2.32

解曰：有為空者，謂欲界、色界、無色界。此中欲界由欲界空，色等亦爾。無為空者，謂無生無住無異無滅。此無為由無為空，相無相空故。從此第四明三世空。

The commentary states: "Emptiness of the conditioned" refers to the desire realm, form realm, and formless realm. Here, the desire realm is empty through the desire realm, and the form realm and others are also like this. "Emptiness of the unconditioned" refers to non-arising, non-abiding, non-changing, and non-ceasing. This unconditioned is empty through the unconditioned, because both having marks and being markless are empty. Next is the fourth [part], clarifying the emptiness of the three times.