The Supernatural is thus not the World of Spirits and Lost Souls, but the World of Jinn

SPIRIT POSSESSION
Another widespread fallacy is the concept of spirit-possession, during which a supposed spirit (of a dead person) occupies the human body and the individual experiences fits and epilepsy. The Shaytaan has used this false belief so strongly to corrupt people's Aqeedah that some of those who believe in spirit possession even commit acts of Shirk, like performing un-Islamic rituals and offerings at the tombs, hanging amulets containing words of disbelief, etc. to protect themselves from possession and to seek treatment.
It should be made known that most of these cases are due to psychological illness, mistakenly understood to be spirit-possession. The reason behind the prevalence of this misconception, to some extent, is the practice of some exorcists, who have made exorcism a way of obtaining money from the common masses. They convince people into believing that they have been possessed by spirits and earn money in the name of treatment. However, real cases of possession are very few and they are due to the Jinn, who occupy the human body and not spirits. And Al-hamdulillah, Allah and His Messenger (sallallahu alaihe wa-sallam) have rightly guided us in this regard; anybody possessed by the Jinn can be cured by the prescribed treatment mentioned in the Sunnah of Allah's Messenger (sallallahu alaihe wa-sallam), Insha'Allah.
The Reality : In light of what has preceded (about the soul and its journey after death in the previous article), it can be undoubtedly said that spirits of the dead do not return back to the world after death. Thus, it is not possible that the spirits can possess the human body. The only possible source, which could be involved in possessing human body, is the Jinn.
Shaikh al-Islam Ibn Taymiyyah (rahimahullah) states in Majmoo al-Fatawa, "The existence of the Jinn is an established fact, according to the Book, the Sunnah and the agreement of the early scholars. Likewise, the penetration of a Jinni into a human body is also an established fact, according to the consensus of leading Sunni scholars. It is also a fact witnessed and experienced by anyone who reflects on it. The Jinni enters the one seized by fits and causes him to speak incomprehensible words, unknown to himself; if the one seized by fits is struck a blow sufficient to kill a camel, he does not feel it."

Evidence for Jinn Possession

Allah says: "Those who eat Riba (interest) will not stand (on the Day of Judgment) except like the standing of a person beaten by the Shaytaan leading him to insanity ('mass')." [Soorah al-Baqarah (2): 275]
In this verse, Allah compares the state of those who eat Riba, on the Day of Judgment, with the one beaten by the Shaytan leading him to insanity. The word used in this verse for insanity is 'mass', which also means devil possession. Since Allah has made the Qur'aan, the most truthful book, it can never contain a false comparison.
Therefore, this verse proves the truthfulness of Jinn-possession. Al-Qurtubee writes in his Tafseer of this verse: "This verse contains proof against those who deny the possession by way of Jinn, claiming that it is a result of natural causes, as well as those who claim that Shaytaan does not enter humans nor does he touch them."
Clear Evidence of Jinn possession from the Sunnah are in a number of authentic tradition, one of which is related by, Ya'la Ibn Murah (radhiallahu anhu), who says: "I saw Allah's Messenger (sallallahu alaihe wa-sallam) do three things which no one before or after me saw. I went with him on a trip. On the way, we passed by a woman sitting at the roadside with a young boy. She called out, 'O Messenger of Allah, this boy is afflicted with a trial, and from him we have also been afflicted with a trial. I don't know how many times per day he is seized by fits.' He (sallallahu alaihe wa-sallam) said: 'Give him to me.' So she lifted him up to the Prophet.
He (sallallahu alaihe wa-sallam) then placed the boy between himself and the middle of the saddle, opened the boy's mouth and blew in it three times, saying, 'In the name of Allah, I am the slave of Allah, get out, enemy of Allah!' Then he gave the boy back to her and said: 'Meet us on our return at this same place and inform us how he has fared.' We then went. On our return, we found her in the same place with three sheep. When he said to her, 'How has your son fared?' She replied: 'By the One who sent you with the truth, we have not detected anything (unusual) in his behavior up to this time…" [Musnad Ahmad (vol: 4, p. 170), and al-Haakim, who declared it Saheeh]

This authentic narration describes how Allah's Messenger (sallallahu alaihe wa-sallam) commanded the Jinn possessing the boy, to leave. Also, the Messenger of Allah (sallallahu alaihe wa-sallam) is reported to have said: "Verily, Shaytaan flows in the blood-streams of Adam's descendants." [Saheeh Muslim (vol: 3, no: 5404)]

Causes of Possession
There could be three main reasons for possession, as suggested by Shaikh al-Islam Ibn Taymiyyah (rahimahullah):

(a) The occasional possession

(b) Majority of the possessions are the result of hatred and revenge of the Jinn, because of some wrong done to him. For example, when humans accidentally harm or hurt the Jinn by urinating on them, by pouring hot water on them, or by killing some of them, the Jinn think that they have been harmed intentionally. Though humans may not realize what they have done, the Jinn are by nature ignorant, very harsh and unstable in their behavior, so they may revengefully punish humans much more than they actually deserve.

(c) Possession sometimes also occurs as a result of plain evil on the part of the Jinn, just as evil and mischief occurs among humans for similar reasons. [See Majmoo al-Fatawa vol: 19, p. 39]
"Jinn mostly gain control over those who have little religious inclination and those whose hearts and tongues faith has deserted. Those whose souls are desolate of the remembrance of Allah and of the formulas of strengthening faith."
EXORCISM to Free a human from Jinn-Possession
To exorcize the Jinn is obligatory according to the principles of repelling oppression, aiding the oppressed, enjoining righteousness and forbidding evil, just as it is with human. [Shaikh Abdul Aziz Ibn Abdillah al-Baaz, al-Mujtama' Magazine, no. 830, 18/8/87, p. 39-41]
A question was posed to Ibn Taymiyah (rahimahullah) regarding the subject, he expressed the same view and added: "… In (exorcism) there is also alleviation of grief and suffering of the oppressed. Allah's Messenger (sallallahu alaihe wa-sallam) is reported by Abu Hurayrah in Saheeh Muslim (vol: 4, no: 6250) to have said: "Whoever relieves a believer of one of the tragedies of life, Allah will relieve him of one of the calamities of the Day of Resurrection…" Jaabir (radhiallahu anhu) also reported in Saheeh Muslim (vol: 3, no: 5456) that when Allah's Messenger (sallallahu alaihe wa-sallam) was asked about incantation, he replied: "Whoever among you is able to help his brother, he should do so."
However, help should be justly rendered according to the methods prescribed by Allah and His Messenger (sallallahu alaihe wa-sallam). For example, Islamically based prayers, words and phrases should only be used in the way they were used by the Prophet (sallallahu alaihe wa-sallam) and his Companions. When commanding the Jinn to righteousness and prohibiting it from evil, it should be done in the same way that man is ordered and forbidden. Whatever is allowable in the case of humans is also allowable in the case of Jinn." [As-Shiblee's Ahkaam al-Jaann, chapter. 53, p.147-8]
Pre-requisites of the Exorcist:
Treatment of fits due to Jinn possession requires two essential factors from the possessed and the healer.
(a) Turning truthfully to Allah alone and having full conviction that the remembrance of Allah and Qur'aanic recitation will effect the person and the Jinn. The stronger the faith, the stronger will be the effect.
(b) Using correct means to drive the Jinn away, as taught by Allah's Messenger (sallallahu alaihe wa-sallam).
For, surely this type of treatment is, in fact, war against the Shaytaan and the warrior will not be able to defeat his enemy unless he fulfills two conditions; that his weapon is sound and sharp, and that his arm is strong. Whenever either of these two conditions is not met, a long sword will be of no value! [See Zaad al-Maa'ad p. 67-69]
"Such a person (who exorcizes the Jinn) is a soldier of Allah, and since exorcism is among the greatest forms of Jihad, he should beware not to help his enemy overcome him by his own sins. If the circumstance is beyond his capacity, he should remember that Allah does not burden a soul beyond its capacity. He should not expose himself to tribulation by taking on what he is unable to handle." [Ibn Taymiyyah, Majmoo al-Fatawa]
Methodology:
The following are some ways of exorcism, which have been deduced from the practice of Allah's Messenger (sallallahu alaihe wa-sallam) and the Sahabah (radhiallahu anhum), any of them may be used to drive the Shaytaan away:
(a) If the possession is due to magic, then the most effective way is to find and undo the charm used in bewitchment.
(b) Address the Jinn and inform him that their acts are either abominable or tyrannical.
(c) Cursing the Jinn
(d) Reciting certain Qur'aanic verses or prayers taught by Allah's Messenger (sallallahu alaihe wa-sallam), like Ayat al-Kursee (Soorah al-Baqarah (2): 255), Basmalah (verbal saying of: 'Bismillah ar-Rahmaan ar-Raheem'), Ta'awwuth (saying "I seek refuge in Allah from the accursed Shaytaan), making Adhaan or Iqaamah, etc.
(e) Beating: If the above-mentioned steps fail to bring the desired results, then the exorcist may strike the possessed individual in order to inflict pain on the possessing spirit. These blows fall upon the Jinn and the possessed human does not feel them

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