"For as he thinketh in his heart, so is he." Proverbs 23:7a (KJV)
Are you a dweller? I can be, especially if something is bothering me. Our thoughts are often a reflection of our hearts. If we think about what we're going to say to get back at the person who has offended us, it shows our heart is in a dark place rather than a forgiving place. If we think about how to make someone's day extra special, it reflects a joyful, giving heart. People often lose sleep because of thoughts running thru their heads. Turn it over to the Lord in prayer and get a good nights sleep. A restful heart is a peaceful heart.
Philippians 4:8, "Finally, brothers and sisters, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things." (NIV)