In Matthew 5:22, Christ talked about progressive levels of anger, from a mere emotion toward a brother, to insults and cursing, with an associated danger attached to each one.
But I say to you that everyone who is angry with his brother will be liable to judgment; whoever insults his brother will be liable to the council; and whoever says, ‘You fool!’ will be liable to the hell of fire.Matthew 5:22
Christ knew how potently, and potently toxic, the effect of anger could wreak in a human heart and in the lives of all people connected to it. Oftentimes, what begins as particular anger at offenses or inconveniences can become so great and undealt with [backlogged] that it gets displaced and disconnected from its original source. This displaced, generalized anger can lead people to be angry with, and curse, others for no reason. Such an advanced angry state is a dangerous thing.