Jesus speaking:

When the unclean spirit is gone out of a man, he walketh through dry places, seeking rest; and finding none, he saith, I will return unto my house whence I came out. And when he cometh, he findeth it swept and garnished.

Then goeth he, and taketh to him 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.

Casting out demons is not the answer for the demon possessed. A decision for Christ is the answer. If the demon possessed person will receive Christ, the demon must leave and he cannot come back to a house occupied by the Saviour.

And it came to pass, as he (Jesus) spake these things, a certain woman of the company lifted up her voice, and said unto him, Blessed is the womb that bare thee, and the paps which thou hast sucked. (In praise of Mary?)

But he (Jesus) said, Yea rather, blessed are they that hear the word of God, and keep it. Luke 11:24-28

…let the word of Christ dwell (take up its life) in you richly…