首楞嚴義疏注經 8.480

8.480

即訟習為因也。黨己覆罪，為他所訟，報在鬼類，託質於人，如世有童子師及巫祝之類，皆為神道傳送凶吉禍福之言，名傳送鬼。此上鬼類其數實繁，考果徵因不過此十。

This is caused by the previously mentioned habit of litigation. Siding with one's faction to conceal crimes, being sued by others, they receive retribution in the ghost kind and lodge their substance in human beings. Like child mediums and shamans in the world, they all transmit words of auspiciousness, inauspiciousness, misfortune, and fortune on behalf of spiritual entities, and are called messenger ghosts. The kinds of ghosts above are indeed numerous, but investigating the fruits and examining the causes, they do not exceed these ten.