Whatever things are true, whatever things are noble, . . .
Negative attitudes are self-defeating.
If a person thinks he won't do well on a test or won't be able to break a bad habit, he probably won't. So too, if we as Christians continually question God's goodness or doubt the ability He has given us to accomplish worthwhile goals, we hinder the Holy Spirit's work in our lives. God wants us to fill our minds with wholesome thoughts that give us a positive outlook on life and make us better people. There is a subtle danger in all of this, however. Positive thinking may be nothing more than a mental exercise or a natural optimism.