妙法蓮華經玄義 7.122

7.122

文云：「皆令得歡喜。」歡喜即利益相，若迹中三乘共十地、別十地，開權顯實，按位妙、入位妙，如是等益，乃至聞壽命，增道損生，皆是迹中益也。乃至中間權實之益，亦是迹益。以迹望本，本亦應有偏圓利益。所以下方菩薩皆住虛空者，皆居寂光，本益也。故本本以垂迹，借迹以知本，不復具記也。

The text states: 'I cause them all to attain joy.' Joy is the mark of benefit. Benefits such as the shared ten stages and distinctive ten stages of the three vehicles within the traces, the opening of the provisional and revealing of the real, the wonder of relying on stages and the wonder of entering stages, and even hearing of the lifespan, thereby advancing on the path and diminishing births—all these are benefits within the traces. Furthermore, the provisional and real benefits of the intermediate periods are also benefits of the traces. Viewing the original source in contrast to the traces, the original source should also have both partial and perfect benefits. The reason why the bodhisattvas from below all abide in empty space is that they all dwell in [the Land of] Tranquil Light; this is the benefit of the original source. Therefore, original source after original source casts down traces, and borrowing the traces one knows the original source; this need not be recorded in full detail again.