金剛經纂要刊定記 7.16

7.16

得勝忍不失者。正明不失義。謂若心住相修諸福德，墮於有漏，此福則失。若心離相修諸福德，成於無漏，此福不失也。

"Attaining superior forbearance, it is not lost." This directly clarifies the meaning of not being lost. That is to say, if the mind abides in marks while cultivating various merits, it falls into the contaminated (sāsrava), and this merit is then lost. If the mind is free from marks while cultivating various merits, it achieves the uncontaminated (anāsrava), and this merit is not lost.