Ok, don't tune out after you read the next sentence. This is the first part of a 4 part series on the anger of God. I want to suggest that many or most people (including pastors and theologians) have a very limited appreciation for the wrath of God.
Most people use God's wrath as simply a backdrop for his love, as a contrasting quality, but one that is not good in itself. It is not as attractive or "useful" to us as, say, love and mercy.
However, if we get God's anger wrong, then God gets less glory. We get less joy.
Most people don't associate Jesus with anger and judgment. Notice, in a parable about God's kingdom, of which Jesus is king, Jesus makes a startling statement I bet your pastor hasn't taught on, "But as for these enemies of mine, who did not want me to reign over them, bring them here and slaughter them before me" (Luke 19:27). Later, we'll see a similar verse in 2 Thessalonians.
In Romans 9, we get some answers. Verse 22-23 says, "What if God, desiring to show his wrath and to make known his power, has endured with much patience vessels of wrath prepared for destruction, 23 in order to make known the riches of his glory for vessels of mercy, which he has prepared beforehand for glory—". Verse 17 is similar, regarding Pharaoh.
The purpose of God wrath and even His making people who are prepared for destruction is for the sake of His glory, to show His power and mercy. In this, the fuller revelation of God's character, we will be forever satisfied. In wisdom, God exalts even in His wrath so that God gets more glory and we get more joy.