Jesus expanded on the true meaning and heart behind some of the commandments God passed on through Moses, opposing what the religious leaders had done by adding their oral traditions and their loop holes. He starts with murder. He said that not only is murder wrong, but the emotions which often lead to murder are wrong as well. Jesus was saying that being angry with a brother or insulting a brother makes someone just as guilty and liable to judgment as actually murdering someone. Unresolved anger can lead us to harbor unforgiveness and bitterness which is one of the most self-destructive forces in the world.