金剛般若經依天親菩薩論贊略釋秦本義記卷上 1.147

1.147

經。何以故　第四勝餘修多羅故勝也。文復有二。先徵後釋。此初徵也。不驚等者。有何奇特名希有也。

Sūtra: Why is this? Fourth, it is superior because it surpasses other sūtras. The text also has two parts: first, an interrogation, and then an explanation. This is the first, the interrogation. As for not being alarmed and so forth, what extraordinary quality does it possess to be called rare?