注維摩詰經 4.124

4.124

什曰：慈雖假想與眾生樂，樂從慈起。還見其受苦，其心悲惻則入悲心，欲令常得此樂。次入喜心，喜心雖是假想而作意欲令常樂，故異於慈心也。復次慈心與樂；喜心直觀其得樂，其心歡喜耳。肇曰：以己法樂，樂彼同悅，喜行也。

[Kumāra]jīva says: Although loving-kindness conceptually gives joy to sentient beings, joy arises from loving-kindness. Returning to see them suffer, one's mind feels sorrow and one enters the mind of compassion, wishing that they may always attain this joy. Next, one enters the mind of joy; although the mind of joy is conceptual, it intentionally wishes them constant joy, and thus differs from the mind of loving-kindness. Furthermore, the mind of loving-kindness gives joy; the mind of joy simply contemplates their obtaining joy, and one's mind rejoices. [Seng]zhao says: Taking one's own Dharma joy to rejoice in their shared delight—this is the practice of sympathetic joy.