Followers of Christ should seek peace and actually pursue it as a lifelong goal. Think for a moment about that person who just gets your blood boiling. How does God feel about that person? Today, ask God to give you His heart regarding that person.
There is a huge difference between believing with one's head and believing with the heart. James 2:19 reveals that even the devil believes in Jesus Christ and trembles. But that does not mean that he has a pure and righteous heart. Is your faith merely an intellectual assent that there is a god out there? Or, is your faith from the heart where you have given Christ your life and you experience a loving and dynamic relationship with God?
The difference between Christian faith and behavioral psychology: A person's behavioral changes do not necessarily mean a changed heart. However, the heart once transformed by Christ's forgiveness of sin changes a person's behavior.