21 Since you have heard about Jesus and have learned the truth that comes from him, 22 throw off your old sinful nature and your former way of life, which is corrupted by lust and deception. 23 Instead, let the Spirit renew your thoughts and attitudes. 24 Put on your new nature, created to be like God—truly righteous and holy. 25 So stop telling lies. Let us tell our neighbors the truth, for we are all parts of the same body. 26 And “don’t sin by letting anger control you.” Don’t let the sun go down while you are still angry, 27 for anger gives a foothold to the devil.
The Bible doesn't tell us that we shouldn't feel angry, but it points out that it is important to handle our anger properly. If vented thoughtlessly, anger can hurt others and destroy relationships. If bottled up inside, it can cause us to become bitter and destroy us from within. Paul tells us to deal with our anger immediately in a way that builds relationships rather than destroys them. If we nurse our anger, we will give Satan an opportunity to divide us. Are you angry with someone right now? What can you do to resolve your differences? Don't let the day end before you begin to work on mending your relationship.