Jesus tells us that anyone who is angry with another, will be subject to judgment.  Don't we all get mad?
Yes, we will get mad.  Its how we behave when we are angry that makes the difference.  What Jesus is saying is that when we get angry with someone, we cant keep that anger.  We cant let it get worse.  We need to forgive.  We need to forgive quickly.

We will also make others mad.  When that happens, we need to ask for forgiveness.
God loves us and He has never done a hurtful thing to us. When we say or do hurtful things to another person, we are hurting God.

Don't make God sad by staying mad.
Forgive those who have hurt you and ask to be forgiven from those you have hurt. Do it quickly.  Ask God to help you.  That would make Jesus very happy