Quran 39:41

“The man who beholds gods while sleeping, or in a wakeful state soon turns mad, and the spirit under whose influence these hallucinations take place is called the celestial spirit. When a person beholds his dead ancestors while he is seated at ease, or lying in his bed, he soon loses his reason, and the spirit which causes this illusion of sensible perception, is called the ancestral spirit. The man who shows disrespect to the Siddhas and who is cursed by them in return, soon runs mad and the evil influence by which this is brought about, is called the Siddha spirit. And the spirit by whose influence a man smells sweet odour, and becomes cognisant of various tastes (when there are no odoriferous or tasteful substances about him) and soon becomes tormented, is called the Rakshasa spirit. And the spirit by whose action celestial musicians (Gandharvas) blend their existence into the constitution of a human being, and make him run mad in no time, is called the Gandharva spirit. And that evil spirit by whose influence men are always tormented by Pisachas, is called the Paisacha spirit. When the spirit of Yakshas enters into the system of a human being by some accident, he loses his reason immediately, and such a spirit is called the Yaksha spirit. The man who loses his reason on account of his mind being demoralised with vices, runs mad in no time, and his illness must be remedied according to methods prescribed in the Sastras. Men also run mad from perplexity, from fear, as also on beholding hideous sights. The remedy lies in quieting their minds. There are three classes of spirits, some are frolicsome, some are gluttonous, and some sensual. Until men attain the age of three score and ten, these evil influences continue to torment them, and then fever becomes the only evil spirit that afflicts sentient beings.

Behold, all souls are mine; as the soul of the father, so also the soul of the son is mine: the soul that sinneth, it shall die.

Let each man raise The Self by Soul, not trample down his Self, Since Soul that is Self's friend may grow Self's foe. Soul is Self's friend when Self doth rule o'er Self, But Self turns enemy if Soul's own self Hates Self as not itself.[FN#10]

He who sees all beings in the Self and the Self in all beings, he never turns away from It (the Self).