金剛經纂要刊定記 5.143

5.143

故偈云下。引證。如是苦行果者。對破疑情也。謂因苦果還苦，因樂果還樂，故不同也。如陶金作器器還是金，和土脫墼墼還是土。前徵：云何此法不成苦果？今此結云：如是苦行故，不成苦果也。

"Therefore the verse says...", etc.: Citing proof. "Such a fruit of ascetic practice": Directly refutes the doubt. This means that a cause of suffering returns as a fruit of suffering, while a cause of joy returns as a fruit of joy; hence they are not the same. Just as when smelting gold to make a vessel the vessel is still gold, and when mixing clay to form a brick the brick is still clay. Previously it queried: why does this teaching not result in a fruit of suffering? Now it concludes: because it is such an ascetic practice, it does not result in a fruit of suffering.