大般涅槃經義記 8.130

8.130

二離性名空，眾生佛性即如來藏，如來藏中廣備法界恒沙佛法，是諸佛法同一體性互相集成，無有一法別守自性，故說為空。空義如是。「第一義空名為智慧」明空與慧更無別體，離相義邊故說是空，覺照義邊是故慧門，故無別體。而第二門，良以說空喜同斷滅，故說為慧。

Second, being free from intrinsic nature is called empty: the buddha-nature of sentient beings is precisely the tathāgatagarbha; the tathāgatagarbha vastly encompasses the buddha-dharmas as numerous as the sands of the Ganges throughout the dharmadhātu; these buddha-dharmas share a single identity of essence and mutually constitute one another, with no single dharma separately maintaining its own intrinsic nature; therefore it is spoken of as empty. The meaning of emptiness is like this. "Ultimate emptiness is named wisdom" clarifies that emptiness and wisdom have no separate essences: on the side of the meaning of being free from marks, it is therefore spoken of as empty; on the side of the meaning of awakening and illuminating, it is therefore the gate of wisdom; hence they have no separate essences. As for the second gate, it is precisely because speaking of emptiness easily accords with nihilistic extinction that it is spoken of as wisdom.