The Jewish religion is based on the first five books of the of the Bible which Jews call the Torah. It tells the story of the formation of a nation around a central belief that only one supernatural being exists. This viewpoint was diametrically opposite to the prevailing primitive belief that everything in nature was possessed by and controlled by spirits.
It was not easy for the Israelites to accept the idea that the very creator of the universe had chosen them and the history described in the Torah and the subsequent books of the Old Testament is one of a continual struggle between the two belief systems. The central question posed by belief in one all powerful god, creator and ruler of the universe is: why suffering? The religions of the surrounding peoples had no difficulty with this question. Good things came from the work of good spirits and bad things came from the influence of evil spirits.
The human race seems to have learnt nothing over the thousands of years of recorded history. We are still killing, maiming, torturing and abusing each other continually inventing better ways of doing it. What causes one human being to inflict pain on another? What madness led to the Holocaust or to the genocides which continue? It is very easy to blame supernatural evil.
Even the original Hebrew writings of the Old Testament were subject to contamination by this concept. Modern Christian translations differ wildly, but the original contains only three or four possible references to a supernatural evil being. We have the reference to the serpent in the Garden of Eden. A couple of sentences in Job describe a "son of god" called Satan who is given the function of causing Job to loose his possessions, family and health to test his faith in God. Academics agree that the name which translates literally as "accuser" actually comes from the legal term for the prosecutor in a court of law. This same name is used in the First book of Chronicles ch.9 v 1 to account for the reason why King David ordered a census, possibly in Psalm 109, (but the JB only refers to someone being put on trial) and in the book of the prophet Zechariah ch.3 v.1 where the "Accuser" is rebuked by an angel.
Against these three or four possible references, the whole theme of the Old Testament is that there is only one God, creator and ruler of everything. No other god exists: the gods of the nations around them are nothing but dumb stone idols.
By the time of Jesus, the Jews had lived for generations under the influence of Greek and Roman culture with their pantheon of gods and explanations of good and evil. We find that the New Testament contains possibly 31 references to "Satan", 51 to the "The Devil" and 4 to "Beelzebub". To the person who believes their translation of the Bible to have been literally dictated by God, these references create a problem. It is a problem I have wrestled with over the years as my understanding of the nature of the Bible has wondered between the two extremes of Liberal and Evangelical theology. I think the most rational explanations for the inclusion of these references is that they are just part of an everyday language that used a lot of metaphors. Jesus does not say "don't be silly, Satan does not exist" but "I watched Satan fall like lightning from heaven" because it was far easier to work within the mind-set of the day.
In the many acts of healing that are recorded in the Gospels, the explanation is often given that an evil spirit has been cast out. I do not take as these as proof that these illnesses are caused by evil spirits, simply that Jesus was working within the common mind-set of the day.
Therefore, after many years of consideration, I am still of the firm opinion that supernatural evil does not exist. Hopefully, I will not be burnt to death for expressing this belief, a fate which would have been almost certain a few hundred years ago. But in this more enlightened age, those who believe in the existence of Satan hold fast to a doctrine that Satan is most powerful in convincing people that he does not exist. To the more irrational of their number, someone who denies the existence of the Devil is obviously under his influence.
The concept of supernatural evil provides a powerful tool for controlling peoples' minds and justifying the persecution of those who do not conform. When nations clash, it becomes a tool with which the leaders of one nation can demonize the whole population of the other. Language is a powerful tool. With the application of a single word, one nation can be divided against another. Simply by naming the USA as Satan, all the thoughts associated with that concept become applied to every US citizen and it becomes a religious duty to murder innocent bystanders.
Religions become vulnerable to derision when they try to explain how nature works in terms of the supernatural. Winds are caused by the sun's heat and the earth's rotation, not by spirits. It took ten billion years from the first moment of creation to the formation of the earth and another four and a half billion years for life to have evolved and modern man appear on the scene. The world was not created by God in six days. Likewise human behaviour can be explained by a combination of psychology, sociology and evolution. We do not need to invent hob-goblins, demons and devils to explain the darker side of our nature.
We are hunter gatherers who have reached the top of the food chain, but still have the reproductive capacity of prey. Once we became the hunters and not the hunted, the human population started to expand beyond the available food supply. When that happened, the laws of nature took over and survival of the fittest became a matter of tribal identity and skill in warfare. What scientists have discovered is that we are not the only species able to form a group identity and develop fighting methods and group strategies for defending and conquering territory. The logical conclusion is that we had these instincts and skill long before we started standing upright and learnt to talk. We humans are different form most other species in that we have developed new regions of our brains able to handle language and learn skills, but the anatomists tell us that our brains have evolved, not by radical change, but by a series of upgrades. When we upgrade a computer, say by fitting extra memory, or adding new software, the computer will only continue to function if the original hardware and software remains intact. It is like this with the brain. The ability to draw maps and navigate would be useless unless all the systems which allow us to walk remained intact and functioning.
It is in our nature to be able to kill humans to defend our territory, just as it is in our nature to kill animals for food. It is in our nature to identify with a family or tribal group as "us" and label every one else as "them" and behave quite differently towards members of the two groups. Unfortunately, language and word based thinking have left us very vulnerable to manipulation of our group identity. Various scientific studies have shown that about 50% of us can be manipulated into inflicting pain on others for their good to the point where we inflict lethal harm.
It is wrong to try to attribute supernatural powers of good and evil to the complex human situation because the way see any act is purely subjective. One cannot think of a more "evil" act than nailing the Son of God to a cross, yet in His own words Jesus pronounced judgement: "Farther forgive them, for they know not what they do."
The love of God is so powerful, so overwhelming, so all embracing; that there is no room in creation for supernatural evil of any kind.