Question: What is the ruling on Tandhir (Invoking Jinn and devils against someone to do him harm) like saying, “Take so-and-so” or “Harm them”? What is the ruling on someone who does that? I heard someone say that whoever seeks the help of the Jinn, their Salaah (Prayer) and Sawm (Fast) will not be accepted. In addition, when they die, funeral prayer should not be offered for them, their funeral should not be followed and they should not be buried in the Muslim graveyards.
Answer: Seeking the help of the Jinn and turning to them to fulfill someone’s needs, such as asking them to harm or benefit a person, is an act of Shirk (associating others with Allaah in His Divinity or worship)… read more here.