金剛經纂要刊定記 6.119

6.119

彼處等者。此明無有一法可名為上。如須彌至大、微塵至小，盡未免於上，以皆有故。如虛空無故，得名無上也。

Regarding "in that place," etc.: this clarifies that there is not a single dharma that can be named "unexcelled." Just as Sumeru is supreme in greatness and a subtle dust mote is supreme in smallness, neither of them escapes having something superior, because they are both existent. Just as empty space is non-existent, it attains the name "unexcelled."