Within the Bible, God is described as wrathful over one hundred times. We see God’s wrath mentioned in Ezekiel 8:18 after God shows Ezekiel the idol worship taking place in the temple precincts. In the same Bible, however, God is said to be merciful. How can the same God be both wrathful and merciful? Aren’t these opposites of each other?
Theologian Norman Geisler, in Systematic Theology, Volume Two: God, Creation, explains in very simple and succinct terms how this is possible.
Wrath and mercy are not incompatible, since they are exercised toward different objects; wrath is on the unrepentant, and mercy is on the repentant. As established previously, God is consistently and unchangeably angry with sin and consistently and unchangeably delighted with righteousness.
God acts mercifully toward those who repent of their sins, while God displays His wrath toward those who are unrepentant. There is simply no inconsistency.
There is a further objection about God’s wrath. Some people cite New Testament passages which speak of Jesus Christ taking the wrath of God for sinners. If Jesus took God’s wrath, then nobody should be subjected to God’s wrath any more. Geisler answers this objection:
This objection is based on a misunderstanding of what Christ did on the cross. The salvation of everyone was not applied; it was simply purchased. All persons were made savable, but not all persons were automatically saved. The gift was made possible by the Savior, but it must be received by the sinner (Eph. 2:8–9; cf. John 1:12). In short, the salvation of all sinners from God’s eternal wrath is possible, but only those who accept Christ’s payment for their sins will actually be saved from it.