It was part of Old Testament prophecy that the coming of Christ would be accompanied by the binding of the forces of darkness when the New Testament age came in (Isaiah 61:1). Demon possession was an awful problem which was completely beyond the power of ordinary men and women to deal with, and when Christ cast out demons he marked himself out as having power which was from above.
Before conversion we cannot ask God because we do not pray effectively. Although men gather in places of worship, their praise to God is not heard because it is not uttered from believing and grateful hearts. It is only dead worship and dead work and the soul is effectively dumb. Some do not ask for new life because they think it will hurt them and take from them all that they value most. ‘I will be less happy than I am now.’
If you decide to put out of your mind the biblical teaching about Satan, about a personal devil, then you have got a lot of explaining to do. You can't account for evil, for its force and its intelligence and its subtlety. You can't account for your own prejudice. Why is man so prejudiced against God? Why would man hurl himself away eternally, invest everything in this life, even though he burns his fingers, even though living for himself disappoints him and hurts him? Why should he turn his back on a gracious God with all the wonderful promises God has made for happiness now, and life for all eternity? Why is it that I find my mind forever fighting to oppose it, and doubts flooding in the moment I think of it? What has God ever done against me? What is there in the Lord that could possibly upset me?
In the times of Christ, there was considerable demon possession. Sometimes people in these days, not aware of the details, are inclined to assume that they simply attached that label to all kinds of illnesses which they didn't understand, and they assume that these were sad cases of sickness of mind, and they were all put into the category of demon possession. But that is not the case at all. Luke, the physician, and others also, under the inspiration of God, describe some of these cases. The symptoms are described, and it doesn't resemble in any way, any condition which we would regard these days as some form of sickness of mind. The features of demon possession were remarkable and unusual. Things akin to demon possession are seen from time to time in some parts of the world, where there is much involvement with the occult, but not resembling anything which we would regard as sickness of mind. There seems to have been a flurry of this just before the coming of Christ, almost as though there was some activity, some frenzy taking place in the demonic world among Satan and his hosts. Demon possession is recorded and spoken of in ancient literature, but it doesn't seem to be as common as it suddenly became just before the coming of Christ. It is as though there was some frenzy taking place in the demonic world among Satan and his hosts, and the Scripture teaches us that one of the signs of the coming of Christ would be to demonstrate his power over demons and over demon possession. So the casting out of demons was one of the sign miracles that Christ did, authenticating himself. Up to that time no one had successfully cast out demons. Power awaited the coming of the Messiah. There has been a minimising of demonic activity of this sort in the gospel age, and this has been a benefit in this age even to the unconverted.
Now again today we are mentally conditioned by our rationalistic educational processes to be shy about things like this and to be rather prejudiced about them. But it should be rather obvious that if there is a God in heaven and if there is a spiritual realm, that if God intervenes into our world, and, as he claims he has done, sends his Son, the Lord Jesus Christ, to make an atonement for us, to teach us about himself, he would perform sign miracles. If Christ had never performed a sign miracle to demonstrate who he was and his mighty power, we would have cynics the world around saying, ‘He was not who he claimed to be, for he did no miracles.’ Things that are normally impossible are possible with God. That is how God demonstrates that he is at work. So the sign miracles were performed clearly by the Saviour, and he could deal cases which were beyond anyone else, and one such case was that of demon possession. And you notice that all these miracles of the Lord were instantaneous. They were carried out quite often in the presence of a crowd, a number of people. They were done at a word; there was no complex procedure; there was never any relapse. Nobody could deny them for generations to come. Even the authorities of those days had to admit that a notable miracle has been done. The deeds of Christ could not be imitated or counterfeited.