Can Demons Re-enter a Person After it is Cast Out?
After deliverance from an evil or unclean spirit(s), some people may fear that these spirits would come back. In fact, Jesus Himself also gave this warning:
When the unclean spirit is gone out of a man, he walks through dry places, seeking rest, and finds none. Then he says, I will return into my house from where I came out; and when he has come, he finds it empty, swept, and garnished. Then he goes forth, and takes with himself 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. Matthew 12:43-45
The Man Possessed by "Legion"
Is there any way to permanently keep these evil spirits out? Fortunately, Lord Jesus has also taught us how to do this. Let us take a look at the man possessed by demons called "Legion".
In Mark 5:2-20, it is recorded that a man possessed by a multitude of unclean spirits collectively named "Legion" was delivered by Jesus. After deliverance, Jesus gave specific instructions to this man which was not recorded in any other deliverance. Jesus said,
Go home to your friends, and tell them how great things the Lord has done for you, and has had compassion on you. Mark 5:19
Why did Jesus gave instructions specifically to this man and not to the others? I believe it is because the man "that had been possessed with the devil prayed him (Jesus) that he might be with Him" (Mark 5:18). Why did he want to stay around Jesus? Probably one major reason was because he was afraid that the demons might come back.
Keep the Unclean Spirits Out
In giving this man specific instructions, Jesus was not only commanding him to glorify God, but He was also teaching him how to keep the unclean spirits out in the following ways.
1. Strengthen the Faith in his Own Deliverance
By continuing to give testimonies, he strengthens the faith in his own deliverance. Since doubt is often the open door through which demons re-enter a person, his continual affirmation will keep them out.
2. Prevent Unbelief in his Friends
Since unbelief in families and friends could create doubt in a person's own healing, giving testimonies to them prevent this from happening by strengthening their collective faith.
3. Praising God Turn Demons Away
Demons cannot tolerate believers giving thanks and praising God. As witnessed by many preachers and evangelists, preaching about God and giving praise to Him often turn the demons away.