Think about this: Since the very beginning of time, when sin entered the world, there has been anger and fighting. Consider how the very first child, Cain, in anger killed his brother, Abel. If it has always been this way, what chance do we have to be people of peace? And yet, that is what the Bible challenges us to be: People of Peace.
It starts with having peace with God. As Romans 5:1 says, "Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ." That is where peace with others has to start. Confessing sin. Claiming Christ as Savior.
God entering your life through repentance and salvation allows the Holy Spirit to take up residence in your soul and begin to change you from being an angry person to one who brings peace to every relationship.