Luke 6:45 As a Man Thinketh so is He

 ⁴⁵A good man out of the good treasure of his heart bringeth forth that which is good; and an evil man out of the evil treasure of his heart bringeth forth that which is evil: for of the abundance of the heart his mouth speaketh. -Luke 6:45 Bible, King James Version

As a man thinks so is he spiritually either good or evil. We rise or fall spiritually in the inner worlds according to the quality of our thoughts and feelings. The devil we must all overcome is our own human mind and emotions. If there is a battle between the mind and the emotions, the emotions usually win therefore the easiest way I believe to take control of the mind and the emotions is to open up the Heart chakra. This effectively closes the lower Solar-plexus chakra of emotion and replaces it with Divine Love. Out of these higher Divine Feelings naturally flow pure thoughts just as evil thoughts naturally flow out of negative emotions such as anger.