摩訶止觀 5.160

5.160

自行安心者，當觀察此心，欲何所樂？若欲息妄，令念想寂然，是樂法行。若樂聽聞，徹無明底，是樂信行。

As for calming the mind in one's own practice, one should contemplate this mind: what does it desire to delight in? If one desires to quiet falsity and make thoughts quiescent, this is delighting in Dharma-practice. If one delights in listening and hearing, penetrating to the bottom of avidyā, this is delighting in faith-practice.