What is anger? Anger is an emotional tool with a purpose, all emotions have purpose: To preserve our personal worth, essential needs, and basic convictions, we are angry because we think we are being rejected or invalidated. Look at Jesus' anger at the temple when he turned over the tables of money changers; we can see anger and its purpose. Jesus' personal worth is being ignored; his basic convictions are being scorned. He accuses them of turning the Temple to a den of thieves through their commercial activities and rejecting the true use of the Temple to worship God. But it is not the only example of Jesus' anger; he address the Pharisees, (Matthew 23), where Jesus calls the Pharisees of hypocrisy, (Mark 3), Jesus heals the man with a weathered hand and is criticized for doing so, his reaction is to defend his actions as just, he rebukes Peter, ( Mark 3), because Peter was stopping Jesus from his mission, all of these examples show Jesus using anger to rebuke the rejection he felt of those who invalidated his message and mission. Jesus uses anger to reprimand those who did not believe. The times when we think Jesus should have been angrier than he seemed to be, like with the woman caught in adultery, woman at the well, we see Jesus' anger as a way of teaching in this anger he does not want to injure their growing spiritual maturity, his anger is to guide and encourage.
Jesus tells us the anger is a sin, yet here are examples of his own anger. Many of the moms with whom I journey feel that anger cannot be "Christian/Catholic”; that to be anger is to be sinful. They are very confused by this. Many of their parents showed very unhealthy patterns of anger; that is the sin Jesus is talking of.