Proverbs 14:17 - "Short-tempered people do foolish things, and schemers are hated." (NLT)
Oh, anger, how you make us do all kinds of crazy things. Anger is a valid emotion. When bad things happen, we sometimes get angry about them at first. However, to let anger take hold means we allow that emotion to drive us to act rashly.
Anger can sometimes drive us to make positive changes. For instance, anger that needed school program was cut can drive us to start a petition or raise money for its return. Instead of letting the anger take hold, we identify the problem and find a solution.
However, anger over things we cannot change can sometimes find a hold on our thoughts and make us destructive. We have to learn that anger is short-lived, and we cannot allow it to make our decisions for us. When we allow our tempers to get control, we say things we do not mean. We do things that can harm us for far longer than the anger lasts. We have to think through what is making us angry. We have to pray on it. It's okay to say we're angry, but not to live in the anger.