大般涅槃經義記 7.51

7.51

第三段中，依前六句次第釋之。「云何不生生不可說」者牒問初句，下釋其相，偏以後生破初不生成不可說。言「不生」者牒初不生，「名為生」者是後生也。不生之時有可生義，云何可得定說。「不生」下重顯之，「何故」問也。「以生故」者，以可生故，不可一向定說不生。

In the third section, it explains them sequentially according to the previous six lines. "How is it that the non-arising arising cannot be spoken of?" cites the question regarding the first line; below, it explains its characteristics, specifically using the subsequent arising to refute the initial non-arising to show that it cannot be spoken of. "Non-arising" cites the initial non-arising; "is called arising" is the subsequent arising. At the time of non-arising, there is the meaning of capability to arise; how could one definitively speak of it? Below "Non-arising," it clarifies it again. "Why?" is the question. "Because of arising" means that because it is capable of arising, one cannot definitively speak of it strictly as non-arising.