A Muslim has to believe in the jinn. They are mentioned in the Qur’an and Hadith. In many instances, they share with us many of our roles and actions. However, it is noticeable nowadays that many people, when they feel anything wrong with themselves, interpret that as a matter of possession by jinn. In fact, many of them will change their mind after they go to a doctor who checks up to find out that the person is diagnosed to have some physical or psychological problem.
Every Muslim is to believe firmly that no one, however great his powers may be, can benefit or harm him unless Allah wills it. Then a Muslim’s best cure, protection, and immunity against the harm of jinn is by practicing Islam, reading the Qur’an and making frequent dhikr and du`a’.

In this context, the following fatwa is issued by Sheikh M. S. Al-Munajjid, a prominent Saudi Muslim lecturer and author, regarding jinn possession: “There are some facts and some illusions connected to the issue of jinn possession, and among most people nowadays the illusions outweigh the facts. There is agreement among Sunni Muslims the jinn can dwell in the bodies of humans, but that does not mean that everyone who has epilepsy is possessed by the jinn, because epilepsy may have physical causes. The pains that many people feel in their bodies cannot be ascribed for certain to the actions of the jinn, rather they may be illusions or something imaginary.

So, a Muslim should not pay any attention to the whispers of the Satan that make he/she think that he/she has done this and that. This is one of the ways in which the Satan deceives the Muslim and makes him/her think that he can control him/her, and that he has powers that in fact he does not possess. This may lead to bad consequences as has happened to many people.

A Muslim has to keep on treating himself with ruqyah, for the Book of Allah is available to him/her. One should recite from it and treat him/herself with ruqyah. Whether one is possessed or not, he/she will undoubtedly benefit from this reading and ruqyah.

If a Muslim goes to someone who is known for using ruqyah as prescribed in Shari`ah and is also righteous and keeps away from deviance and myths, there is nothing wrong with that and it may be a means of being healed from this problem.

A Muslim has to seek the help of Allah and pray to Him and beseech Him to prevent the plots of the devils among mankind and the jinn from harming him/her. Man is always in need of his Lord, and Allah is Able to rid one of these thoughts, illusions and facts that are harming him/her.”

Shedding more light on the protection against and the immunity from the harm of jinn, we’d add the following:
“Because jinn can see us while we cannot see them, the Prophet (peace and blessings be upon him) taught us many ways to protect ourselves from their harm. They are seeking refuge of Allah from the accursed shaytan, reciting surat Al-Falaq and surat An-Nas, and reciting the words taught by Allah in the Qur’an. Allah Almighty says, “And say: My Lord! I seek refuge in Thee from suggestions of the evil ones. And I seek refuge in Thee, my Lord, lest they be present with me.” (Al-Mu’minun: 97-98)
Saying Bismillah (in the Name of Allah) before entering one’s home, eating or drinking, and having intercourse will keep Satan from entering the house or partaking with a person in his food, drink and sexual activity. Similarly, mentioning the name of Allah before entering the toilet or taking off one’s clothes will prevent the jinn from seeing a person in a state of undress or harming him. The Prophet (peace and blessings of be upon him) says: “To put a barrier that will prevent the jinn from seeing the `awrah of the sons of Adam, let any one of you say ‘Bismillah’ when entering the toilet.” (Reported by at-Tirmidhi)
Strength of faith and religion in general will also prevent jinn from harming a person, so much so that if they were to fight, the one who has faith would win. Ibn Mas`ud (may Allah be pleased with him) says: “A man from among the Companions of Muhammad met a man from among the jinn. They wrestled, and the human knocked down the jinn. The human said to him, ‘You look small and skinny to me, and your forearms look like the front paws of a dog. Do all the jinn look like this, or only you?’ He said, ‘No, by Allah, among them I am strong, but let us wrestle again, and if you defeat me I will teach you something that will do you good.’ The human said, ‘Fine.’ He said, ‘Recite (the verse): “Allah! There is no God save Him, the Alive, the Eternal. Neither slumber nor sleep overtaketh Him. Unto Him belongeth whatsoever is in the heavens and whatsoever is in the earth. Who is he that intercedeth with Him save by His leave? He knoweth that which is in front of them and that which is behind them, while they encompass nothing of His knowledge save what He will. His throne includeth the heavens and the earth, and He is never weary of preserving them. He is the Sublime, the Tremendous.” (Al-Baqarah: 255) The human said, ‘Fine.’ He said, ‘You will never recite this in your house but the shaytan will come out of it like a donkey breaking wind, and he will never come back in until the next morning.
’” (Reported by ad-Darimi)