妙法蓮華經玄義 3.34

3.34

頂法者，色界善根，有動、不動，住、不住，有難、不難，斷、不斷，退、不退。就動乃至退者，有二：下者是煖，上是頂。彼不動乃至不退者為二：下者是忍，上者是世第一法。復有說者，應言下頂。所以者何？在煖法頂，故名頂。在忍法下，故名下。復有說者，如山頂之道，人不久住。若無難，必過此到彼；若遇難，即便退還。行者住頂不久，若無難必到忍；有難退還煖。猶如山頂，故名頂。

As for the phenomenon of Summit, it is a wholesome root of the form realm, having movement and non-movement, abiding and non-abiding, having difficulties and non-difficulties, severing and non-severing, retrogression and non-retrogression. With regard to movement up to retrogression, there are two: the lower is Heat, and the upper is Summit. Those of non-movement up to non-retrogression are two: the lower is Acceptance, and the upper is the phenomenon of Foremost worldly phenomena. Another says: it should be called "lower summit." Why is this? Because it is at the summit of the phenomenon of Heat, it is called Summit; because it is below the phenomenon of Acceptance, it is called lower. Another says: like the path on a mountain summit, people do not stay long. If there are no difficulties, they will certainly cross over from here to there; if they encounter difficulties, they immediately retrogress and return. The practitioner abides at Summit not long: if without difficulties, they will certainly reach Acceptance; if there are difficulties, they retrogress and return to Heat. Like a mountain summit, it is therefore called Summit.