首楞嚴義疏注經 10.8

10.8

觀，緣也，雖有根識緣諸境界，而不想像繫念在意，故如其鏡照物無跡，但虛受、虛照、虛應而已。亦可如鏡照於光明，雖鑒無影，故云虛受。

'Viewing' means taking as object. Although there are sense faculties and consciousnesses taking various realms as objects, he does not form conceptions or bind his thoughts upon them in mind; therefore he is like a mirror reflecting things without leaving traces, merely emptily receiving, emptily illuminating, and emptily responding. It can also mean that just as a mirror reflects light, although it mirrors there is no shadow; hence it says 'emptily receives'.