大般涅槃經疏 29.9

29.9

「迦葉白佛五種六種」下，第二番正明因性生善，先問、次答。問中，先牒前七六五佛性；次正問中意既在未來，云何言有而能生善？佛答為三：一雙譬、二雙合、三雙結。初又二：先舉過去業故現受樂報、次舉未來業未生故終不生果。「有現在煩惱」下，二雙合，又二：初一句合前過去業現在樂果，即合現在。以煩惱故能令斷善，必由過去。今言現在煩惱者，本是過去，今來現在。次「若無煩惱」下，合第二譬未來業未生終不生果，即合未來佛性因緣故能生善根。「是故斷善根人」下，三雙結，如文。

From "Kāśyapa addressed the Buddha: The five kinds and six kinds" onward is the second round, directly explaining the production of good on the basis of the causal nature, first questioning and next answering. In the question, he first reiterates the previous sevenfold, sixfold, and fivefold buddhadhātu; next, in the direct question, the sense is that since it is in the future, how can it be said to exist and be able to produce good? The Buddha's answer has three parts: 1. A pair of similes; 2. A pair of applications; 3. A pair of conclusions. The first also has two parts: first, citing how due to past karma one presently receives pleasurable retribution; next, citing how because future karma has not yet arisen, it ultimately does not produce fruit. From "There are present afflictions" onward is the second part, the pair of applications, again having two parts: The first sentence applies to the previous past karma and present pleasurable fruit, namely applying to the present. Because of afflictions one can sever good, which must depend on the past. Now when it says "present afflictions," they were originally past, and now have come to the present. Next, from "If there were no afflictions" onward applies to the second simile that future karma has not arisen and ultimately does not produce fruit, namely applying to the buddhadhātu as cause and condition in the future being able to produce roots of goodness. From "Therefore one who has severed the roots of goodness" onward is the third part, the pair of conclusions, as in the text.