請觀音經疏闡義鈔 2.48

2.48

From "a bodhisattva" downward reveals the perfect [teaching]. "This emptiness is also empty": because one has the upāya of the provisional and the middle, one does not stagnate in emptiness; this is being able to empty emptiness, hence it is said "this emptiness is also empty." Because one has upāya, there is no defiled attachment. From "and capable of" downward: because there is no defiled attachment, emptiness is immediately the provisional. "Completely cultivating the myriad practices and thoroughly penetrating the Buddha Path" means penetrating those myriad practices as being the principle of the three truths; it is through this wisdom that one is guided to advance toward bodhi.