If you would read my earlier posts you would see that I have put on the shield of faith, the armor of God. Having faith is the only way to fight off Satan. I didn't contradict myself, stop kidding yourself.
Here's how it works....
A person with faith reads the bible and "clears out his house" because the evil cannot stand the truth and leaves, the person is clean for a while, as their faith protects them. Then as the shield wears off, the evil spirit returns to its home because it couldn't find a place to go, bringing with it 7 more evil spirits than before so that it doesn't get kicked out again.
A person with no faith hears the truth, the demons hate it, leave, but because there is no faith, no shield, no armor of God, so the demons come back almost instantly, bringing back more evil than before to again, make sure they don't get booted out again.
Satan and evil cannot get into my mind much at all anymore because of my faith, I sweep my house, what evil does exist, and my shield protects me for a long time, the evil comes back only to find my understanding of truth has increased so it gets scared from that and leaves, eventually, all evil will leave and never come back (assuming you achieve the faith Christ had)
Yes, this is in the Bible, and yes, it's more true than the thoughts running through your mind right now.