瑜伽師地論略纂 4.12

4.12

「業天」者，即世人多以為善惡由天，理實由業，說業名天。初由悲故，後起慈心，而與其樂，故唯言慈。

'Karma-heaven': Most worldly people believe that good and bad depend on heaven, but in truth they depend on karma; karma is metaphorically called heaven. First due to compassion, later a mind of benevolence arises to bestow happiness upon them; hence only benevolence is mentioned.