Does it really matter what I think about as long as I do what is right?
Jesus says that thinking about evil is just as bad as doing evil. God looks at the condition of your heart, not just the things you do. Unclean thoughts pollute your heart and mind which  grieves your Heavenly Father, who is  holy and righteous. When your thoughts stray toward anything that’s wrong, choose to turn them towards good instead. Your faith and some positive thinking can be transformed into positive beliefs, and powerful in reshaping your mind, heart and the character of your life.
Don’t worry about anything, instead, pray about everything. Tell God what your thoughts are. His love and peace will guard your heart and mind. Fix your thoughts on what is true, honorable, and worthy of praise. Let God transform you into a new person by changing the way you think, then you will learn to know God’s perfect will for you.