Exorcism
In Christianity, exorcism is the practice of casting out demons. In Christian practice the person performing the exorcism, known as an exorcist, is often a member of the Christian Church, or an individual thought to be graced with special powers or skills. The exorcist may use prayers and religious material, such as set formulas, gestures, symbols, icons, amulets, etc. The exorcist often invokes God, Jesus and/or several different angels and archangels to intervene with the exorcism. Protestant Christian exorcists most commonly believe the authority given to them by the Father, Son, and Holy Spirit (the Trinity) is the source of their ability to cast out demons.
Exorcism in Islam
Prohibited techniques often utilize "shirk", which is found in practices that prepare amulets or talismans. This is prohibited because "shirk" is the sin of practicing idolatry or polytheism i.e. the deification or worship of anyone or anything besides the singular God. Many times Qur'anic verses are added throughout the recitation when using these objects in order to 'mask' their "shirk". However, God believes he has provided sufficient cures in executing an exorcism, therefore exorcists should not have to rely on methods involving "shirk". Additionally, individuals seeking exorcism should avoid magicians or soothsayers because these magical practices go against Islamic Law.