[kosta50]

The word shed in various biblical version translated as "dol," "demon" or "devil" (in Hebrew simply means "god," a ruler, one who can exert control.

OT Judaism doens't know demonology of the later, Post-Babylonian apocalyptic age. Christian demonology is derived mainly from the so called Old Testament "Apocrypha," books which have thrie roots in messianic (apocalyptic) Judaism; books considered scripture by the early Church and to this day by the ROman Catholic and Orthodox Churches.

So, while OT refreences to idols are cursory, and have to deal with worshiping false gods, demonology goes into full blown afterburn in the NT, which ha snothign to do with worshiping idols, but being completely taken over by these spirits. With pages and pages of references to illnesses and cured related to demons.

It seems to me that some illnesses can be caused by demons or be the physical and psychological side-effects of possession and obsession by demons; but this is rare

They can?. What demons? What illnesses? Can we name them? My Blue Letter Bible lexicon makes a note (with my emphases):

In the NT, these [demons] are persons, afflicted with especially severe diseases, either bodily or mentally, (such as paralysis, blindness, deafness, loss of speech, epilepsy, melancholy, insanity, etc.) whose bodies in the opinion of the Jews demons had entered, and so held possession of them as not only to afflict them with ills, but also to dethrone the reason and take its place themselves; accordingly the possessed were wont to express the mind and consciousness of the demons dwelling in them; and their cure was thought to require the expulsion of the demon.

Driving out demons is part of Jesus' ministry and also the duties of the disciples. He even leaves all believers wiht these words:

And these signs will accompany those who believe: In my name they will drive out demons; they will speak in new tongues; 18they will pick up snakes with their hands; and when they drink deadly poison, it will not hurt them at all; they will place their hands on sick people, and they will get well [Mark 16:17-19]

Do you have any of these "signs?" How do you know then that you are believer, when the Bible is so clear what "those who believed" will do and see?

[Of course you do realize that Mark 16:9-20 do not exist in the earliest reliable sources, so God only knows how many of these demonic references are latter-day addiions by scribes and monks, pretending to be words of God]

Claiming that some illnesses can be caused by demons requires equally extraordinary evidene. I am open to seeing such evidence, although form what I have seen it is without substance.

[maryz]

Claiming that some illnesses can be caused by demons requires equally extraordinary evidence

I think you're "loading the deck" here, assuming without argument that material causality is the only kind, omitting reference to final, formal, efficient causes. This is, of course, appropriate to scientific research (I guess), but not really satisfactory even in areas of normal life, never mind theology. And it's a common view in our reductionist age!

[koinonia]

I only have one example (hence rare). A young man named Louis whom I met. He complained of not being able to sleep due to extremely violent and scary nightmares every time he went to sleep. Obviously I began to ask him about his faith life, if he prayed, if he believed in Jesus. At the name of Jesus the pupils of his eyes rolled back into his head and, for all practical purposes Louis was not present to me for a good minute--then his eyes rolled back and, not aware that anything had happened he complained of now having a severe migraine headache. In the conversation that followed, I had to avoid that NAME so he wouldn't disappear, he told me that his parents were satanists and had consecrated him to the devil.

I later found out that he went to a priest to get help, and when the priest showed him a crucifix Louis went to the floor violently and began convulsing and foaming at the mouth. He was referred to an exorcist priest and, thank God, was successfully delivered. He now longer has migraines and siezures.

Why? because, in his case, they were caused by demons and once delivered from the demons they went away.

That certainly does not mean that everyone with migraine headaches should set up an appointment for deliverance prayers! Or that a person with epilepsy is possessed! I think Louis' case is exceptional, but clearly an example of physical "illnesses" caused by demons.

Jesus healed a woman hemorraging--no mention of casting out demons, he healed Peter's mother in law--no mention of demons; and ten lepers and various paralytics and blind--no mention of demons, and the man with the withered hand--no mention of demons, etc.. Obviously there were sicknesses directly caused by demons in the Gospels and in those cases Jesus healed them by delivering them from their root cause, the devil.