金剛經纂要刊定記 6.171

6.171

偈云等者。彌勒偈也。於中半釋秦偈、半釋魏偈，意云：見聞是識，但能緣於色聲，佛非色聲，故不可知。

"The verse says..." and so forth is Maitreya's verse. Within it, half explains the Qin verse and half explains the Wei verse, meaning: seeing and hearing are consciousness, which can only take form and sound as objects; the Buddha is not form and sound, hence he cannot be known.