To what extent do jinn affect humans, and can they harm a person, especially if he is weak in faith? What is the meaning of "mass" (possession)? Can jinn appear in the form of a human? What is the best way to avoid evil jinn? Is a person's fear of hearing verses about magic and jinn an indication of possession or magic?

The effect of jinn and their harm upon humans is affirmed by the consensus of the Ahl al-Sunnah wa al-Jama’ah (mainstream Sunni Muslims), as indicated by the words of Allah the Almighty in Surat Al-Baqarah: "Those who consume interest will not stand [on the Day of Resurrection] except as one stands who is being beaten by Satan into insanity." The jinn may take different forms, such as humans or animals (like a black dog, a black cat, or snakes), but a person's reaction and fear upon hearing verses about magic and jinn do not necessarily indicate possession by jinn or being afflicted by magic.