摩訶止觀 4.130

4.130

六度、道品亦具三義：助道名護助；助道發正道，即是外護。正、助合故，即是同行。依此正助不失規矩，通入三解脫門，即是教授。

The six pāramitās and the aids to the path also possess the three meanings: aiding the path is called protecting and aiding; that the aids to the path give rise to the correct path is the external protector. Because the correct and the aiding combine, this is the fellow practitioner. Relying on this correct and aiding without losing the rules, and penetrating into the three gates of liberation, this is the teacher.