Matthew 5:21 – 23 You have heard that it was said to those of old, you shall not murder; and whoever murders will be liable to judgment. But I say to you that everyone who is angry with his brother will be liable to judgment; whoever insults his brother will be liable to the council; and whoever says, ‘You fool!’ will be liable to the hell of fire.
Anger itself is not a sin, but how we respond to that anger can be. When trying to understand a passage one must keep it in context. Many passages seem to say one thing but if you keep them in the context of their chapter, book, or the whole Bible it becomes obvious they do not mean what it first appears. These verses above, standing alone, seem to say that simply being angry with another person is sinful. However, The Bible tells us that we should not sin in our anger (Psalm 4:4) and Jesus got angry (Mark 3:5) so anger must not be a sin in and of itself.
Sin comes into the picture when we become angry for wrong reasons or when we respond to anger in the wrong way. Jesus became angry when supposedly godly people acted hypocritically or did something to hinder God’s Kingdom. If you get angry about the things that make God angry then it is a holy anger. If your anger comes from selfishness or not getting your own way then it is sinful anger.
Even holy or righteous anger can go wrong if we respond in a manner that does not glorify God. For example, if you are angry because of an injustice being done then it is a righteous anger because God gets angry at injustice. If in your anger you curse someone or do harm to someone then your righteous anger is darkened by a sinful act.
Anger is a powerful emotion. It can spur a person to take action that can make a change for good. It can also cause us to do or say things we regret later. We must learn to keep our anger under control or it can control us. When anger controls us is usually leads to sin.
Lord, let me live a holy life. Cause me to keep a control on my temper so that I will do nothing to dishonor You or hinder Your kingdom from advancing.