大方廣佛華嚴經疏 34.29

34.29

第二「菩薩見」下正起慈悲。初明興悲，謂見苦應拔；後「復作」下興慈，謂無樂應與。既言具苦，必知無樂故。

Second, from 'The bodhisattva sees...' onward, the direct arousal of benevolence and compassion. First, it clarifies the raising of compassion, which means seeing their suffering and knowing they should be rescued; second, from 'He further thinks...' onward, the raising of benevolence, which means seeing they lack joy and knowing it should be given to them. Since it is stated that they are endowed with suffering, one must know that they lack joy.