首楞嚴義疏注經 8.281

8.281

此下五名，今是一也。以佛於無見頂放光，化佛說神呪故。此表一心具體相用。大，體也；佛，相也；頂光化佛，即是用也。細釋配法，即開題中悉怛多等云白傘蓋，藏心無染曰白，遍覆一切曰傘蓋。實相智慧是尊重法，楷定正邪，唯佛與佛乃能究盡，名無上寶印。三世諸佛以此明照諸法實相，竪窮橫遍具無漏德，名清淨海眼。此上總約理智立名也。

Of the five titles below, this is the first. Because the Buddha emitted light from his invisible crown and an emanated buddha spoke the divine mantra, this signifies that the one mind is endowed with substance, marks, and function: 'Great' is the substance; 'Buddha' is the mark; the light from the crest and the emanated buddha are the function. Explaining the match to dharmas in detail, as in the opening title, Sitātapatrā means White Parasol: the undefiled storehouse mind is 'white'; covering all completely is 'parasol'. The wisdom of the true mark is an exalted dharma that determines the correct and the deviant, which only buddhas together with buddhas can fully fathom; hence it is named the 'Unexcelled Precious Seal'. The buddhas of the three periods illuminate the true mark of all dharmas with this, extending vertically to the limits and horizontally everywhere, possessing uncontaminated virtues; hence it is named the 'Pure Sea-Eye'. The above generally establishes the name in terms of principle and cognition.