Stock Photo: A Mexican woman yells desperately during the exorcism rite performed at the Church of the Divine Saviour in of Mexico City, Mexico, 31 May 2011 Exorcism is an ancient religious technique of evicting spirits, generally called demons or evil, from a person. A Mexican woman yells desperately during the exorcism rite performed at the Church of the Divine Saviour in of Mexico City, Mexico, 31 May 2011 Exorcism is an ancient religious technique of evicting spirits, generally called demons or evil, f