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.
Exorcist II: The Heretic
Philip Lamont, a priest struggling with his faith, attempts to exorcise a possessed South American girl who claims to "heal the sick". However, the exorcism goes wrong and a lit candle sets fire to the girl's dress, killing her. Afterwards, Lamont is assigned by the Cardinal to investigate the death of Father Lankester Merrin, who had been killed four years earlier in the course of exorcising the Assyrian demon Pazuzu from Regan MacNeil. The Cardinal informs Lamont (who has had some experience at exorcism and has been exposed to Merrin's teachings) that Merrin is facing posthumous heresy charges because of his controversial writings as Church authorities are trying to modernize and do not want to acknowledge that Satan exists.