妙法蓮華經玄義 10.137

10.137

四法開合者，未是圓四門，眾生不解，開別四門，乃至三藏四門，傳傳令入如前。

Opening and merging four dharmas: originally it is the four gates of the perfect; sentient beings do not understand, so one opens the four gates of the distinctive, down to the four gates of the tripiṭaka, causing them to enter successively as before.