首楞嚴義疏注經 10.379

10.379

廣說不盡者，即前文云「若我說是佛頂光聚悉怛多，呪從旦至暮音聲相連，字句中間亦不重疊，經河沙劫終不能盡。」此顯經義及持者功德皆不可量也。依我下以能得最極之果、能離內外魔事，用勸如說而行也。斯則弘持經者所得所離，唯佛與佛乃能知之。

"Even if I were to expound it at length... I could not exhaust it" refers to the earlier passage: "If I were to speak of this Sitātapatrā of the cluster of light atop the Buddha's crest, with sounds continuing from dawn to dusk without repeating syllables or phrases, even after kalpas as numerous as the sands of the Ganges, I could not exhaust it." This reveals that both the meaning of the sūtra and the merit of the upholder are immeasurable. From "rely on my..." onward, because one can attain the supreme fruit and leave behind inner and outer demonic deeds, it encourages practicing as taught. Thus, what is obtained and what is abandoned by those who propagate and uphold the sūtra can only be known by a Buddha together with a Buddha.