起信論疏筆削記 12.21

12.21

結難測。論　唯佛知者，欲言其淨，則九相紛然；欲言其染，則一味無變。若非佛智孰能知焉？自性心難了者，以能隨緣成染故。所染難了者，以即染而常淨故。言甚深智者，即八地已上，以覺轉現，少分而知。然從初地亦得少知，以證真故，故前云：若證法身，得少分知。

Concluding that it is difficult to fathom. The Śāstra states: "Only the Buddha knows": if one wishes to speak of its purity, the nine marks are manifold and bustling; if one wishes to speak of its defilement, it is of a single taste without change. If not for the Buddha's wisdom, who could know it? The mind of self-nature is difficult to understand because it can accord with conditions and become defiled. That which is defiled is difficult to understand because while being defiled, it is constantly pure. When it mentions "extremely profound wisdom," this refers to the eighth ground and above, where by awakening to the transforming and manifesting, one knows it in small part. However, from the initial ground onward one also attains a small degree of knowledge because of realizing the true; hence it was said before: "If one realizes the dharmakāya, one attains a small part of knowledge."