This book asks: Do we need the devil and demons to explain adversity, bad behavior, crime, disease, evil, and failures? Must we understand all allusion to the devil and demons in the holy Scriptures in a literal sense? Do these beings really exist? Or is Satan only a personification of all that is atrocious, bad, criminal, disagreeable, evil, frightening, gross, horrible, indecent, and wrong? It often happens that people live in fear and terror for the devil and his helpers, all sorts of evil spirits, sorcerers, wizards, and witches. How realistic is this fear? This is another ground-breaking book by theologian and scholar Albertus Pretorius. As in his previous books, he manages to provide new insights regarding controversial biblical subjects. In this case, he deals with the existence or non-existence of Satan and sinful spirits. The author explores what the conventional beliefs on Satan entail, as well as what a critical investigation of the holy Scriptures of Judaism, Christianity, and Islam can teach people of the twenty-first century about these perilous and pestilential personages.