Tonight in our Bible Study, we are going to begin a study on Demon Possession Today: To Cast or Not To Cast. David Powlison has an excellent book entitled Power Encounters which is extremely helpful and my study on this subject has been helped greatly from his insights.
When the Bible speaks about evil or the powers of evil, it speaks about it two ways: situational and moral, seen succinctly in Ecclesiastes 9.3: This is the evil in everything that happens under the sun [situational]: the same destiny overtakes all. The hearts of men, moreover, are full of evil [moral] and there is madness in their hearts while they live and afterward join the dead.
Moral evil is what people believe and do. It is sin, wickedness, unrighteousness which we are responsible for before God. Situational evil is what happens to us as we live in this fallen world or to put it another way, it is the result of living in a broken creation.
This is necessary to understand because when we read the Gospels and Acts, we read Jesus confronts demon possessed people who are, among other things, blind, deaf, convulsing, cutting, screaming, and foaming. Jesus is confronting those who are experiencing situational evil, the sad fruit of life under Satan's kingdom, the one who seeks to destroy and bring pain, tears, and torment. A classic case is Job as his possessions, children and finally health are all taken from him so he curses the day of his birth because of his suffering.
When Jesus casts out demons, he is meeting the kingdom of darkness head on and in a spectacular way he is reversing the curse of Genesis as he gives relief of suffering (thus showing His love); he is revealing that HE is LORD GOD ALMIGHTY and we should pay attention and believe; and he is giving an object lesson for the coming blessings of the kingdom for all who repent and believe.