"Jesus said to His disciples, 'Go into all the world and preach the gospel to all creation?..These signs will accompany those who have believed: In My name they will cast out demons????" (Mark 16:15-17).
Men and women have been possessed by demons from the beginning of human history. But we read of people being delivered from demons only after Jesus came. Now that Christ has defeated Satan on the cross, anyone can be totally delivered from demons in Jesus' Name - just like anyone can have his sins totally forgiven in Jesus' Name. Jesus wanted His disciples to proclaim this dual good news all over the world - that people could be delivered from the guilt of their sins as well as from demons. However, I never had faith to deliver people from demons until I was baptized in the Holy Spirit and was convinced that Jesus had defeated Satan on the cross.
One of my first encounters with an evil spirit, interestingly enough, was when I was speaking to students at a Bible-College. (Jesus cast out demons during synagogue- meetings!) I had experienced a great anointing in speaking that morning and had just concluded my message and asked everyone to bow in prayer. Suddenly one of the students in the last row of the hall got up and started dancing in the aisle. I realized immediately that this was a demon trying to distract the students from responding to the message. Since everyone was bowed in prayer, I knew that any loud rebuke of the demon would make the students lift their heads and look around and be distracted. So I whispered under my breath (so softly that even those sitting immediately behind me on the platform did not hear), "In Jesus' Name, sit down." Immediately the young man (who was nearly 40 feet away from me) sat down. I then continued with my closing prayer. I left the Bible-college after the meeting and never discovered who that student was. Some months later, I got a letter from another country. The person wrote saying that he had been possessed by a demon while in a temple some years earlier, and had then become a Christian and joined the Bible-college (at which I had spoken). He identified himself as the student who had stood up at that meeting and then wrote, "I sat down when you told me to sit down"! I was amazed to read that sentence - because his ears certainly did not hear my whisper that day, for he was too far away. But the demon within him had heard my words - and obeyed.
The Lord taught me two lessons that day about demons. First of all, that demons have very good hearing and so we don't have to shout at them (like many people do) when casting them out! Secondly, that if our life is clean and we have faith in Christ's victory over Satan at the cross, we need command the demons just once - and they will leave immediately. One does not have to keep on commanding them (as many people do). Jesus cast out demons with a single sentence: "When He spoke a single word, all the demons fled" (Matt.8:16-Living Bible). If demons do not leave after a single command of ours, it would indicate that our faith is weak. Then we need to go away and fast and pray first (Matt.17:21).
On another occasion, a sister from our church brought a lady to my home for prayer because she was having some problems. My wife and I spoke with the lady and then I asked her to repent of her sins and to receive Jesus as her Saviour. I also asked her to speak to Satan and tell him, "I don't belong to you now. Jesus defeated you on the cross". (I ask all who want to be saved to say this to Satan). All of a sudden, she contorted her face, and looked at me fiercely and changed her voice and said, "I was not defeated on the cross". Until then I had not even suspected that she had a demon, for she had spoken to us gently. But when I realized that a demon was there, I immediately said to the demon, "You are a liar. You were defeated on the cross. Get out of her in Jesus' Name." The demon left immediately. I knew that it had left, because when I asked the lady a second time to say the same words to Satan, she said it immediately, without any hesitation.
That day I learnt a third lesson about Satan and demons - that they don't like to be reminded that they were defeated on the cross. So I decided thereafter, that I would remind Satan frequently that Jesus defeated him on the cross. I also decided to teach this glorious truth to all believers. (We have to speak these words to Satan, since he cannot hear our thoughts or what we say in our mind.) It is because many Christians either don't know, or don't believe, in Satan's total defeat on the cross (as written in Colossian 2:15 and Hebrews 2:14) that they live in fear of him and are afraid that he might harm them in some way.