Have you ever seen a more angry culture? Even a time where CHRISTIANS seem more identified as angry people? Me neither.
The Pharisees were deeply concerned about the external... good behavior. For instance... "Do Not Murder!"
Easy-peasy, right? Well, Jesus comes along and says "Hey, could we have a conversation about your anger? You think your hiding it but God knows and you seem to have a murderous heart. Your judging, condemning, raging and unforgiving."
Once again the law of Christ... the law of LOVE asks so much more of us. How in fact can you think you'll maintain a vertical relationship with God when you have a broken horizontal relationship with someone created in God's image?