Emotions are God-given gifts and have been given to us for our benefit. However, like everything else, it must be stewarded properly. When we talk about anger, it usually leads us to ask if being angry is a sin. The Bible says:
(Ephesians 4:26-27 KJV)
26 Be ye angry, and sin not: let not the sun go down upon your wrath:
27 Neither give place to the devil.
Anger is not necessarily sinful. All emotions have the capacity for both good and evil. It’s not so much the expression itself, but the motive behind the emotion and how it is being applied. Emotions are a part of how we communicate, and they serve as warning signals to others and to ourselves. Imagine a world without anger; it would be hard to let others know of any offense they may have committed, as well as the gravity of it. We can look at anger like a stop light. It allows us to show others that an action or word has offended us, and that it should be stopped. In such a case, it is very helpful in reminding people of lines that should not be crossed.
There is also a type of anger that the Bible considers acceptable. Most call it “righteous indignation.” For one, God has often been angry for the right reasons. You can find in the Scriptures that wickedness angers God (Psalm 7:11 KJV).
(“God judgeth the righteous, and God is angry with the wicked every day.”)
In the New Testament, the greed and disrespect for God’s holiness shown by the money changers and animal sellers in Jerusalem made Jesus very angry (John 2:13-17 KJV) .
(“And the Jews’ passover was at hand, and Jesus went up to Jerusalem,  And found in the temple those that sold oxen and sheep and doves, and the changers of money sitting:  And when he had made a scourge of small cords, he drove them all out of the temple, and the sheep, and the oxen; and poured out the changers’ money, and overthrew the tables;  And said unto them that sold doves, Take these things hence; make not my Father’s house an house of merchandise.  And his disciples remembered that it was written, The zeal of thine house hath eaten me up.”)
God cannot sin, so therefore, His anger is always righteous and just, unlike the anger of man. Thankfully, our God is slow to anger, and abounds in love (Psalm 145:8 KJV) .
(“The Lord is gracious, and full of compassion; slow to anger, and of great mercy.”)
Human anger can cause unthinkable destruction for oneself and others if we allow it to master our hearts. When combined with envy, hatred or pride, anger can result in a murderous outcome, like what happened between Cain and Abel (Genesis 4:1-15). Anger can destroy both a Christian’s relationship with God and the lives of other people.
There are ways that we can manage anger without resorting to sin. When an offense makes us angry and we want revenge, we should remember that vengeance is for the Lord, not us. We should allow God to mete out justice and have trust in Him.
(Romans 12:19 KJV)
Dearly beloved, avenge not yourselves, but rather give place unto wrath: for it is written, Vengeance is mine; I will repay, saith the Lord.
We can keep ourselves from giving in to anger if we learn to bear with one another. In doing so, we become patient with people, find ways to overlook offense, and put real value into the relationship.
(Colossians 3:13 KJV)
Forbearing one another, and forgiving one another, if any man have a quarrel against any: even as Christ forgave you, so also do ye.
Overcoming evil with good can pacify the very hostile effects of anger and prevent grudges. Responding in this way can make us win people over, rather than lose them. We should hate sin, not the sinner, and we should rid ourselves of sin, not of people.
(Romans 12:20-21 KJV)
20 Therefore if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing thou shalt heap coals of fire on his head.
21 Be not overcome of evil, but overcome evil with good.
Lastly, we cannot manage anger on our own, nor do we have the capacity to bring lasting change for ourselves or others. We need the help of the Holy Spirit. When we listen and allow the Holy Spirit to work with us on our anger, we start to bear His fruits.
(Galatians 5:22-26 KJV)
22 But the fruit of the Spirit is love, joy, peace, longsuffering, gentleness, goodness, faith,
23 Meekness, temperance: against such there is no law.
24 And they that are Christ’s have crucified the flesh with the affections and lusts.
25 If we live in the Spirit, let us also walk in the Spirit.
26 Let us not be desirous of vain glory, provoking one another, envying one another.
However, this does not happen overnight. In order to keep ourselves from frustration and self-condemnation, we have to understand that fruits don’t instantly grow. It needs cultivation and nurturing. That’s the good thing about the fruits of the Spirit, they’re not our fruits. They are His. This means that He is the one bearing the burden of our change. If that was left to us and our sinful nature, it would be impossible. The most powerful supernatural manifestation of the Holy Spirit is a changed life!