大般涅槃經義記 9.153

9.153

自下第二知生善根。於中有三：一知眾生根轉不定。「如來具足知諸根力」總以標舉，「故能分別上中下根」略顯知相，「能知轉」等廣顯知相，「是故」下結。二知諸根生斷不定。「以不定故，或斷還生」順明不定，「若根定」下反明不定，「是故」下結。三隨知行答。迦葉先問，「佛具根力，定知善星當斷善根，以何因緣聽其出家」。佛答有三：一遮其現罪故聽出家，在俗為王當壞法故。二生其當善故聽出家，遠生未來出世善故。「若不出家亦斷善」等舉損顯益，「今出家」等彰益異損。三「是故」下結，先順後反。

From here down, the second part is knowing the arising of roots of goodness. Within this are three parts: First, knowing that sentient beings' faculties shift unpredictably. "The Tathāgata is fully endowed with the power of knowing the faculties" generally sets it forth; "hence he can distinguish superior, middling, and inferior faculties" briefly shows the aspect of this knowledge; "able to know shifting..." and so forth broadly shows the aspect of this knowledge; from "Therefore..." downward is the conclusion. Second, knowing that the arising and severing of the faculties are unfixed. "Because they are unfixed, some are severed and arise again" directly explains the unfixed nature; from "If the faculties were fixed..." downward explains the unfixed nature by negation; from "Therefore..." downward is the conclusion. Third, responding in accord with what he knows of their actions. Kāśyapa first asks, "The Buddha is endowed with the power of faculties and definitely knew that Sunakṣatra would sever his roots of goodness; for what cause and condition did he permit him to leave the household life?" The Buddha's answer has three parts: First, to prevent his present wrongdoing he permitted him to leave the household life, because if he remained in secular life as a king he would destroy the Dharma. Second, to generate his future goodness he permitted him to leave the household life, because it distantly gives rise to future supramundane goodness. "If he did not leave the household life, he would also sever goodness..." and so forth adduces the harm to reveal the benefit; "Now having left the household life..." and so forth manifests the benefit in contrast to the harm. Third, from "Therefore..." downward is the conclusion, first affirmative and then negative.