Demon
The contemporary Roman Catholic Church unequivocally teaches that angels and demons are real beings rather than just symbolic devices. The Catholic Church has a cadre of officially sanctioned exorcists which perform many exorcisms each year. The exorcists of the Catholic Church teach that demons attack humans continually but that afflicted persons can be effectively healed and protected either by the formal rite of exorcism, authorized to be performed only by bishops and those they designate, or by prayers of deliverance, which any Christian can offer for themselves or others.
Exorcism
In Taoism, exorcisms are performed because an individual has been possessed by an evil spirit for one of two reasons. The individual has disturbed a ghost, regardless of intent, and the ghost now seeks revenge. An alive person could also be jealous and uses black magic as revenge thereby conjuring a ghost to possess someone. Members of the fashi, both Chinese ritual officers and priests ordained by a celestial master, perform Chinese rituals, in particular, exorcisms.