God's very nature indicates that He could not possibly accept or overlook sin. Since His very nature is pure, He must hate sin and respond with righteous anger. This is the anger that is pure. It does not hold malice, spite, or revenge. It is to give us, His followers, knowledge that we have sinned, then gives us the opportunity to repent, and covers that sin with the very blood of Jesus Christ.
I think it is very different than most of the anger that we, as people experience. Our anger is usually unjust and contains some degree of malice. This is evidenced when we get angry with another driver on the road, our children for being annoying, or our spouse for just ??????