What does the Bible say about demonic oppression? What is the difference between being demon possessed and demon oppressed? Some folks claim evil is more active around Halloween time. But can demons really do much harm to Christians?

What is the difference between being demon possessed and demon oppressed?

OLAADEGBU:
What is the difference between being demon possessed and demon oppressed?

I think Demonic possession is when demonic entities gains the Will of a host whether directly or indirectly to dwell inside the body of a living person and manipulate the person to act in a certain manner, as in the case of the Simon the sorcerer in the book of Acts 8:9 and in Acts 16:17 we are told about a Damsel possessed with the spirit of divination which was used for sorcery too. These two cases are examples of demonic possessions. Also the case of the Child brought to the Apostles when Jesus went up the mountain to meet Moses and Elijah whom the Apostles couldn't cast the demons out.

But dominc oppression is demonic activites of evil spirits against someone from without. Anyone they can not enter, they hinder and cause blockades.
Case in point; Daniel in the book of Daniel 10:13. Demons oppresses Christians more who they can't possesse by causing hinderances, delays, frustrations, disappointments, and hardships. They do this by working not in those they hinder, but in those from whom help should come from.

Satan couldn't enter Daniel like he entered the Astrologers, but, he hindered Angel Gabriel whom he knew will not engage him in battle.

Satan pushed the Astrologers in Babylon to instigate the King to pass a decree which will implicate Daniel, hence kill him by throwing him into the Lions Den.

Satan moved Hamman to oppress Modicai and plot his dead.