Some people are unwilling to let go of a grudge. That was the case of Edom. He was unwilling to forgive his brother.
Amos 1:11 Thus saith the Lord; For three transgressions of Edom, and for four, I will not turn away the punishment thereof; because he did pursue his brother with the sword, and did cast off all pity, and his anger did tear perpetually, and he kept his wrath for ever:
Keeping a Grudge
Some people are unwilling to let go of a grudge. That was the case of Edom. He was unwilling to forgive his brother. As a result he went to war with him. It was so bad that he was never willing to forgive. He kept his wrath for ever against his brother. Keeping a grudge like Edom is not a good thing. He may well have been “justified” in his mind that he should have wrath toward his brother. That did not wash with God though. As a result of this wrath toward his brother, God said he would not turn away the punishment He had planned for Edom. When God gets to the point where there is not forgiveness, that is bad.
Nip it in the Bud
Wrath needs to be nipped in the bud before it grows out of control like it did for Edom. Once it gets so big, it could likely stick with you for the rest of your life. Even when you know you should get right and want to get right, it is hard to get rid of the wrath that always seems to be there for some. When you get rid of charity and pity for your brothers and sisters in Christ, that is a dangerous place to be. The Bible says we are not to let the sun go down on our wrath. Anger will eventually start to tear and naw at you. There is not a good place to hide anger. Be sure to nip wrath in he bud so it does not grow to the point where it starts to draw you down.