首楞嚴義疏注經 8.483

8.483

十因六報皆是純情所為，情既下沈，故墜地獄。地獄治久，情盡上昇，故云業火燒乾上出為鬼。鬼心輕燥，業火所餘，自妄業招，非他所得。菩提心中皆如空華耳。

The ten causes and six retributions are all wrought by pure emotion. Emotion having sunk downward, they fall into hell. After being disciplined in hell for a long time, as emotion is exhausted they ascend, which is why it says, 'When the fires of karma have burned them dry, they emerge above as ghosts.' The ghost mind is light and restless, the residue of karmic fires; it is brought on by one's own false karma, not something obtained from another. Within the bodhi mind, all are merely like flowers in space.