大毘盧遮那成佛經疏 13.6

13.6

警覺諸佛令憶本誓願也。如來昔立如是決定大願，修此真言行者，皆當如持建立，令速滿所願。我今如是修行故，警發諸佛，當念本所立誓願也。

It alerts the Buddhas to recall their fundamental vows. In the past, the Tathāgatas established such definitive great vows: those who cultivate this mantra practice should all be upheld and established as [vowed], causing their wishes to be quickly fulfilled. Because I now practice in this way, I alert and awaken the Buddhas to remember the fundamental vows they established.