成唯識論掌中樞要 2.165

2.165

悔離欲捨者，《法華經》第二舍利子云：「我從昔來終日竟夜每自剋責，而今從佛聞所未聞未曾有法，斷諸疑悔。」「悔」者，是法疑悔，非煩惱也。

Regarding abandoning remorse upon detachment: in chapter 2 of the Lotus Sūtra, Śāriputra says: "From the past onwards, all day and night I constantly reproached myself; and now, hearing from the Buddha this unprecedented Dharma never heard before, I have severed all doubts and regrets." "Regret" is doubt and regret regarding Dharma, not an affliction.