摩訶止觀 6.176

6.176

今觀無明亦復如是。觀二觀智，當彼破惑，名之為「智」。今望中道，智還成惑。此惑是中智家障，故言「智障」。又此智障於中智，中智不發，故名「智障」。前言智能障，後言智被障。例如六十二見，見名「慧性」，慧即世智；若望無漏，此慧性與見思合，能障於真。此二諦智與無明合，障於中道，亦復如是。又能障是惑，所障是中智，能所合論故言「智障」。

Now contemplating avidyā is also like this. One contemplates the wisdom of the two contemplations: when it breaks those delusions, it is named 'wisdom'. Now looking toward the middle way, that wisdom turns back into delusion. This delusion is an obstruction belonging to the middle wisdom; therefore it is said to be an 'obstruction by wisdom'. Moreover, this wisdom obstructs the middle wisdom so that the middle wisdom does not arise; therefore it is called an 'obstruction of wisdom'. The former refers to wisdom being able to obstruct; the latter refers to wisdom being obstructed. For example, among the sixty-two views, a view is called the 'nature of discernment', and discernment is mundane wisdom; if looked at with respect to the outflow-free, this nature of discernment combines with [the delusions of] view and thought and is able to obstruct the true. This wisdom of the two truths combining with avidyā obstructs the middle way, and it is also like this. Furthermore, that which can obstruct is delusion, and that which is obstructed is the middle wisdom; discussing the active and the passive together, it is therefore called the 'obstruction of wisdom'.