金剛經纂要刊定記 4.134

4.134

非但者。不獨也。凡即六道眾生，聖即三乘賢聖，依有淨穢、正即凡聖，為對依報故重牒之。諸法雖多不出此四，雖舉四法該一切也。此釋經中，凡所有相皆是虛妄。恐人聞說身相非相，將謂唯獨佛身，今言凡所以遮局見。

Regarding "not only": it means not solely. 'Ordinary' refers to sentient beings of the six paths; 'noble' refers to worthies and nobles of the three vehicles. The dependent environments have pure and impure; the primary [retributions] are the ordinary and the noble. To contrast with the dependent retribution, it is reiterated here. Although the many dharmas are numerous, they do not exceed these four; although four dharmas are mentioned, they encompass everything. This explains 'all marks whatsoever are empty and false' in the sūtra. Lest people hearing that the physical marks are not marks assume this applies solely to the Buddha's body, the word 'all' is used here to ward off a narrow view.