仁王般若經疏 1.141

1.141

惑前已空故者，如來已出眾惑之外，故云惑前已空。又解：未斷煩惱時本來寂滅，故云惑前已空。佛得三無為果者，總舉三德也。智緣滅者，名數緣滅無為；非智緣滅者，非數緣滅無為；虛空者，法性虛空無為。薩婆若果空者，明佛果體空。

As for "because delusion was already empty beforehand": the Tathāgata has already emerged beyond all delusions; hence it says "delusion was already empty beforehand". Another interpretation says: when afflictions are not yet severed, they are fundamentally quiescent and ceased; hence it says "delusion was already empty beforehand". As for "the Buddha attains the three unconditioned fruits": this generally adduces the three virtues. "Cessation through deliberative wisdom" is called pratisaṃkhyā-nirodha asamskṛta; "cessation not through deliberative wisdom" is apratisaṃkhyā-nirodha asamskṛta; "space" is ākāśa asamskṛta of the dharmatā. As for "the fruit of sarvajñā is empty": this explains that the substance of the buddha-fruit is empty.