[The Idols of the Pre-Islamic Period]

Likewise, the idol-worshippers are addressed by devils, and the same happens to anyone who seeks rescue from a dead or absent person, or who prays to the deceased, or who thinks that supplicating at his grave is better than doing so in homes and mosques.

They even relate a ḥadith which, by unanimous agreement of the specialists, is a fabrication: “When matters overwhelm you, turn to the people of the graves.” It was coined by those who opened the door to shirk (polytheism).

Among the innovators and the polytheists—and those who resemble them from the idol-worshippers, the Christians, and the misguided Muslims—there occur at shrines certain phenomena they imagine to be miracles, whereas they come from the devils. They may place a pair of trousers beside the grave and later find the legs tied together, or they bring an epileptic to the site and see that his demon has left him. The devil does this only to mislead them. Yet if someone recites Āyat al-Kursī (the Throne Verse) there with sincerity, all of this is nullified, for pure monotheism drives the devil away.

For this reason one of them was once carried aloft in the air; when he exclaimed, “lā ilāha illā Allah” (there is no deity but Allah), he fell. Similarly, a man might see the grave split open and a person emerge; he assumes it is the deceased, but it is in fact a devil.

This is a vast subject that cannot be covered fully in this place.

[The Devils’ Caves]

Because withdrawing to caves and deserts in this manner is an innovation that neither Allah nor His Messenger has legislated, devils have come to frequent caves and mountains—such as the Cave of Blood on Mount Qāsiyūn, Mount Lebanon on the Levantine coast, and Mount al-Fatḥ,