大方廣佛華嚴經隨疏演義鈔 71.10

71.10

疏「謂喜樂等」者，喜樂生於貪，憂苦生於嗔，捨根生於癡。後於此類煩惱而有勝用，故多煩惱染根。

Regarding the commentary's phrase “Meaning joy, pleasure, and so forth,” joy and pleasure arise from greed, sorrow and suffering arise from anger, and the faculty of equanimity arises from delusion. Afterward, they have dominant functions with respect to afflictions of this kind; hence, they are defiled faculties with abundant afflictions.