Be ye transformed by the renewing of your mind. Romans 12:2

“People often manufacture their own unhappiness by the negative manner in which they think about things. Work with
your mind, exercise disciplinary control, and re-slant your thoughts for happier living. Drain the mind, by consciously conceiving of yourself as dropping out every destructive thought, every fear, every inferiority feeling. Picture your mind as completely empty. Then start filling it with thoughts of God, and of Christ, thoughts about every good and pleasant thing. Practice this new habit regularly twice every day, morning and evening, to counteract the older and negative habit of allowing unhappy things to occupy your mind. In due course, unhappy thoughts will not feel at home in your mind, and happy thoughts will transform you.”
-- Dr. Norman Vincent Peale