Exp: You are called to give a speech about anti-smoking speech, but you are someone who smokes. What happens is you will start to engage in counter attitudinal advocacy, which means giving out opinions apart from what you believe, like stop smoking, it's dangerous for health. These are also reasons outside their beliefs, which is external justification. Now because of this, they start to see the internal justification and try to bring their attitude in line with their behavior.