Are people possessed by demons today? What is the modern Christian perspective?
There was a very prolific writer on this subject named Kurt Koch in the early part of the 20th century. He initially started investigating problems people were having in southern Germany (similar to the Appalachia area of the US). In these regions it was not uncommon for people to practice the using of charms, spells, and other things associated with demonic activity. As a result people would become influenced, oppressed, and even possessed.
People in these regions were more like those living in tribal areas where intentionally contacting, communicating with, and invoking evil spirits was a more common practice.
Since the practices that bring people into demonic contact were severely abandoned in the latter part of the 20th century, it can seem now as if these conditions were just superstition. While most people consider demonic activity to be a sort of fairy tale, there are those who over emphasize demonic activity such that they see themselves as a sort of crusader that has to bind demons in every room they enter.
Today there is an increase in the cases of demonic influence, oppression, and even possession as a result of an increase in the practices that bring people into contact with spirits.
Things like meditation to contact spirit guides (often done as an imagery exercise where people are just told that what they are contacting is just an expression of themselves). There is an increase in people participating in practices such as automatic writing where messages come through (similar to an Ouija board but using hand writing - TV psychic James Van Praagh gave classroom instruction on this practice on his cable show). The effects of these practices are often diagnosed as mental problems and treated with medication.
It is important for the Christian to remember that he cannot be demonically possessed.
1 John 4:4 Ye are of God, little children, and have overcome them:
because greater is he that is in you, than he that is in the world.
As the modern or developed world turns more rapidly from Christ and embraces practices that bring them more and more into contact with evil spirits, it should be expected that there will be a corresponding increase in those with demonic afflictions.
It is beginning to be more popular to consider exorcisms today. However, these are of limited benefit because the only permanent "cure" is to be filled with the Holy Spirit.
Luke 11:24-26 When the unclean spirit is gone out of a man, he
walketh through dry places, seeking rest; and finding none, he saith,
I will return unto my house whence I came out. And when he cometh,
he findeth it swept and garnished. Then goeth he, and taketh to him
seven other spirits more wicked than himself; and they enter in, and
dwell there: and the last state of that man is worse than the first.