Many people are afraid to express their anger. They believe, falsely, that if they open up to it, it will overpower them and control them and it will be with them forever. Ironically, by trying to keep it bottled up, it does control them, because it expresses in several ways that can make for a living hell. Their anger often comes out sideways --- similar to how boiling water sometimes runs over t
he side of a pot. They become angry in random situations and at people they often don't want to hurt and for which they feel guilty when they do. They are not really angry at the "outer" circumstances or person. This is only a trigger which reminds them and brings up the anger they have buried that is related to something in the past, often from childhood. Do you notice how these people constantly "spill" over the pot and get angry at random things? The only way to release the anger is to go to the true source of it.
The second way that unexpressed anger can make for a living hell is with depression. If you are a person who never gets mad, who believes that anger is "bad," this will cause depression as that anger is turned inward. Do not be afraid of your anger. If you are expressing it sideways, like the boiling pot, you do have a responsibility to not hurt others with this sideways anger and to go to the source. Also, do not be afraid of anger at God. He can take it --- He welcomes it, because clearing out these old patterns and false beliefs, especially those you have around Him, brings you closer to Him. Remember, God is Love, an emotion. We have to be able to process, authentically express, and release when appropriate, ALL of our emotions, "good" and "bad," to know Him.