Stop being bitter and angry and mad at others. Don’t yell at one another or curse each other or ever be rude.
Ephesians 4:31 (CEV)
Bitterness is a deeply buried unresolved anger of the heart. It is a slow and imperceptible poison that creeps into the soul, and if left unchecked, it has the potential to bring huge damage or harm to everything in its path. Unforgiveness breeds bitterness. Our inability to forgive can lead us to commit horrible or unthinkable acts.
The Bible includes several examples and stories of people like Saul, Herod, and Job's wife whose lives were ruined because they were unable to let go of bitterness and resentment to experience God's goodness. Don't be angry or resentful, no matter how legitimate you believe your reasons are! It is not worthwhile in the long run. Leave it to God and stay away from exacting vengeance and retribution!
Make sure that no one misses out on God’s grace. Make sure that no root of bitterness grows up that might cause trouble and pollute many people.
Hebrews 12:15 (CEV)
Grace is the cure for the poison of bitterness.
When God's grace reigns in your heart, He can transform your bitter memories into sweeter ones, your hurts into hope, and your grudges into goodwill. Staying bitter requires the same amount of energy as showing love. Both call for commitment and dedication, but only one leads to life and righteousness.
If someone has offended you, it is right and wise to give the person the opportunity to apologise for their actions before praying together. In doing so, you overcome Satan's two most potent weapons: accusation and deception.
Sometimes you can be the one who offends someone without even realising it. They may not forgive you—but God will. Remember that your righteousness is not based on your capacity to do good, but on His ability to help you live righteously before Him, and that will give you the grace to grow strong in the Lord and the strength to extend grace to others.