"Demons" and "Devils" -Part 1 - Invisible Causes
The Greek word translated as "demon," daimonion, has taken a very different meaning today than it had in Jesus’s time. In his era, a daimonion was literally a "spirit" or, more precisely, a “divine power” or a “lower divine being,” but Jesus most frequently used the word in a more specific way, a more Judean way. Because the King James Version (KJV) translated this word as “devils” while most modern Bibles use the term “demons,” we will look at quotes from the New International Version (NIV). This will avoid the confusion of this Greek word with a different Greek word that is also translated as “devils.” Both of these terms are also confused with “Satan.” See this article on "satanas".
Today, we have a wealth of words to refer to invisible and "non-material" beings that exist independently of any individual. We call some key invisible cause “germs” and “viruses.” We call other concepts “phobias,” “manias,” “obsessions,” and so on. In Jesus's time, many of these concepts were described as "demons." Because we call alcohol "spirits," a drunk might be described as "possessed by spirits." This is surprisingly close to how Jesus used the Greek word, daimonion.
The Greek Words
The Greek word daimonion (δαιμόνια) technically means “something belonging to a demon." More generally, it was used to refer to controlling spiritual power, inferior to that of the gods. It is from the root noun, daimôn, which is also translated as "demon." In Greek, neither daimonion nor daimôn necessarily mean "evil." It was quite the opposite. In the Stoic philosophy, it was the voice of reason inside of us. Plato described his inner voice of conscience as a daimon. The word was used to mean "knowing" and "skilled" in the sense that we might say, "He is a demon poker player." As an adjective, it meant "miraculous", and "marvelous." It was used as an honorific, "good lady" or "good sir". On the spiritual side, it refers to "visitations of heaven" and the "ways of the gods". In its verb form, it meant "to be possessed by a god."
However, in the Greek Old Testament, the Septuagint, daimonion was used to translate several different Hebrew words meaning "idols" ('ĕlîl, אֱלִיל) “shades” (šēḏ, שֵׁד) and for "disease" (deḇer, דֶּבֶר) The last is most important because it was seen as the invisible cause of disease. Today. we might call these invisible causes a “virus” or “bacteria” or “genetic mutation.” Its association with disease gave this word unavoidable negative connotations in the time of Jesus among the Judean who were focused on purity.
In English, the word, “daemon” is still used in the sense of the Greek word, daimonion. While it is also used as an alternate spelling for “demon,” it also means, according to Webster, “an attendant spirit,” “a supernatural being whose nature is intermediate between that of a god and that of a human being”, and “one that has exceptional enthusiasm, drive, or effectiveness.” These are all very close to the meaning in Greek.
How did the positive Greek idea of daimonion become the negative idea in Jesus's time? The verb form of this term means "to be possessed by a god". To the Jews, these "gods" were false, idols, false ideas, delusions. Being possessed by them was to be deluded. From that small step, the term “having a demon” became a general description for mental disorders. They didn't have our own vocabulary for psychological problems. Nor did they have a vocabulary for bad habits and addictions that take on a life of their own.
This Greek word is used only thirteen times by Jesus, the most frequently in the context of “casting our demons.” It usually appears in the plural, but it is used twice in the singular. Jesus uses the term generally to describe the invisible power that causes disease, both physical and mental. He connected it with the more general idea of "spirit" (pneuma - See this article) which is an even broader idea of invisible power. For example, in Matthew 12:27,
NIV And if I drive out demons by Beelzebul, by whom do your people drive them out? …
Listeners Heard: And if I myself toss out the invisible causes of disease with "Beelzebub!" with what do those sons of yours toss them out? Through this, they themselves will be judges of you.
However, Jesus goes onto describe the tossed out causes of disease as an “unclean spirit” in Matthew 12:43”
NIV: When an impure spirit comes out of a person, it goes through arid places seeking rest and does not find it.
Listeners Heard: When, however, that unclean invisible power exits out from this man, he passes through dry places, seeking rest and doesn't discover it.
This idea of the spirit as an invisible being that is “unclean” is consistent with our view of germs. It was also consistent with the Judean concept of purity much of which focusses on avoiding potential causes of disease.
What power can overcome this invisible cause? Another invisible power, that of the Divine. Let us go to Matthew 12:28:
NIV: But if it is by the Spirit of God that I drive out demons, then the kingdom of God has come upon you.
Listeners Heard: If, however, with an invisible power of divinity, I myself toss out invisible causes of disease, immediately, it reaches out as far as you, this realm of the Divine.
Notice how Jesus use the word usually translated as “God” without an article here, so “a divine” instead of “the Divine.” The Greek thought of daimonion as a form of divine power. The Judeans saw the Divine as the source of everything so, in a sense, they agreed. In a sense, the invisible power of the Divine is the source of all other invisible power.
Daimonion as Mental Illness
The majority of Jesus’s uses of daimonion refer to “casting out demons” (the list is here). "Casting out demons" describes about seven of Jesus’s thirty-seven miracles. When those cases are described, they always seem to refer to people with mental disorders including epilepsy. Of course, some physical disabilities, such as the inability to speak, walk, or even see could also be psychological. The view of “having a demon” fits both the Greek sense of daimonion as, "voices within us" and the Judean sense, "the invisible cause of a disease." There was some invisible force at work affecting these people’s minds.
What they describe then as being “possessed by a god," today we describes as being "possessed by a mania” or some other psychological term. We should realize, however, that most of these terms are very new. “Possession by demons” was a common explanation of mental disorders until only the last few hundred years. Today, we are finding ways to cast out many of these demons through the use of drugs, and drug addiction has become a much more common demon.
We still talk about people fighting against their internal demons today. We do this in the context of discussing mental disorders. If the Jesus story was being written today, it would be filled with stories referring to people with "addictions", "troubled minds", "schizophrenia", "mental disorders," and, especially, "delusions." The terms would be more technical because we view our society as more scientific, or perhaps just more psychological. However, the real delusion here is that we have a better and more honest understanding of the human mind and the human spirit today than people did two thousand years ago. What we really have is a new way of talking about what we don't understand. Our pretense of understanding is expressed in different terms than the pretense of understanding in Jesus’s era.
Jesus's use of these terms for various mental delusions was often in response to others who used these terms. For example, in Matthew 12:27 above, he was responding to what his opponents said about him, explaining his miracles. When he had the choice, he preferred using people’s own terms to talk them about how their world. He kept his introduction to new ideas to a minimum, reserving them for concepts such as “the realm of the skies,” which was hard enough for people to grasp. He wasn't endorsing those terms or their world-view as much as he is communicating in the language of the people of his era.
There is, of course, a lot more to say about this subject because the idea of “demons” is much less outdated today than we think.