首楞嚴義疏注經 5.275

5.275

初以單空空於諸相，故云入非。次以重空空於空相，故云非盡，無亦空也。已上五人依根證入畢。

First, one empties all marks through single emptiness, hence it says 'enter into negation'. Next, one empties the mark of emptiness through doubled emptiness, hence it says 'negation is exhausted', non-being also being empty. The realization and entry relying on the faculties by the above five persons is concluded.