Reading from the Book of Philippians 4:8
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. 9 Whatever you have learned or received or heard from me, or seen in me—put it into practice. And the God of peace will be with you.
The Bible presents detailed instructions on what we should be thinking about. You can see from Philippians 4:8 that we are instructed to think on good things, things that will build us up and not tear us down.
Our thoughts certainly reflect our attitudes and moods. Everything the Lord tells us is for our own good. He knows what makes us happy and what makes us miserable. When people are full of wrong thoughts, they are miserable, and I have learned from experience that miserable people usually end up making others miserable also.
Take a personal inventory on a regular basis and ask yourself, "What have I been thinking about?" Spend time examing your thought life. Think about thinking.