The most powerful tool that you have right now in your life, in your body is your mind. That's why the enemy fights you in your mind. The devil doesn't have to tie you up for you to be bound, he just has to tie up your head with stress, with worry, with aggravation, with low self-esteem, with pettiness, with anger, with hostility, with rebellion and he can make you physically sick because your mind is sick.