仁王護國般若波羅蜜多經疏 2.209

2.209

解曰：慈悲等者，由無嗔等善根相應所利無量，義如前解，憐愍化也。從此第三明四弘願。

Exposition: "Loving-kindness, compassion," and so forth: through corresponding with wholesome roots such as non-anger, what they benefit is immeasurable; the meaning is as explained before, which is transforming through pity. Third from here is explaining the four vast vows.