注大乘入楞伽經 2.206

2.206

言能知難知之所以也。以智慧力了諸地相善達句義者，有了因也。無邊佛所廣集善根者，有緣因也。本有正因由是現前，自然明見妄習流注，故云能知。

This explains the reason why it can be known and why it is difficult to know. Discerning the characteristics of the various bhūmis and having good mastery of the meanings of phrases through the power of wisdom constitutes the revelatory cause (jñāpaka-hetu). Having extensively accumulated roots of goodness in the presence of boundless Buddhas constitutes the contributory cause (sahakāri-hetu). The originally existent primary cause (kāraṇa-hetu) is thereby brought to the fore, and one naturally sees clearly the stream of false habits; hence it is said that they "are able to know it."