You are from God, little children, and have overcome [evil spirits]; because greater is He who is in you than he who is in the world (1 John 4:4).
When you came to life in Christ, Satan didn't curl up his tail and pull in his fangs. He is committed to foul up your life through his deception to "prove" that Christianity doesn't work, that God's Word isn't true, and that nothing really happened when you were born again.
You don't have to be a defenseless hockey puck at the mercy of Satan and his demons. God has already supplied the protection you need to ward off any and every attack in the spiritual realm. You just need to know what God has provided and to apply it to your own experience. Your best defense against the god of this world is to live a righteous life in Christ.
Some Christians are a little paranoid about evil powers, suspecting that demons lurk around every corner just waiting to possess them. That's an unfounded fear. Our relationship to demonic powers in the spiritual realm is a lot like our relationship to germs in the physical realm. We know that germs are all around us: in the air, in the water, in our food, in other people, even in us. But do you live in constant fear of catching some disease? No--unless you're a hypochondriac! You know enough about wellness to eat the right foods, get enough rest, and keep yourself and your possessions clean. If you live a balanced life, your immune system will protect you.
It's the same in the spiritual realm. Demons are like little invisible germs looking for someone to infect. We are never told in Scripture to be afraid of them. You just need to be aware of their reality and commit yourself to live a righteous life in spite of them. Should you come under attack, deal with it and go on with life. Remember: the only thing big about a demon is its mouth. Demons are habitual liars. In Jesus Christ, the Truth, you are equipped with all the authority and protection you need to deal with anything they throw at you.
Lord, I know that living a righteous life is my pathway to experiencing freedom. I renounce Satan's lies and choose righteousness today.