Whole libraries of books have been written to answer that profound question. This is nowhere near a complete or adequate answer, but just a few key thoughts in response:
- When God created the world, it was “very good” (Genesis 1:31), but the whole creation, not just people, was broken by sin. Not everything that happens necessarily reflects God’s will.
- Sin brings consequences. Some bad things that happen result from sinful actions, ultimately including death (Romans 6:23).
- When sin disrupted the good order of creation, it produced a kind of disorder or chaos (e.g., Genesis 4). So, some bad things happen with no clear cause or reason. To experience that unpredictability and the anxiety it causes drives home the fact that we do not finally control our own lives, but receive them entirely as a gift from God. As Job poignantly asked his wife, “Shall we receive the good at the hand of God, and not receive the bad?” (Job 2:10)
- Creation is so infected by sin that if God wiped out all evil, it would mean destroying everything in it, including us! God promised after the Flood never to do that again (Genesis 9:11). God “lets bad things happen” because his ultimate goal is to redeem all creation from sin, not to destroy it because of sin (Romans 8:19-21). Paradoxically, God’s mercy, not any lack of care, drives Him to tolerate some “bad things” until the plan of salvation is finished.
- God let the ultimate bad thing happen to Jesus by sending him to the cross to suffer a death he did not deserve, in order to forgive us and rescue us from condemnation. God allowed evil to triumph on the cross, but only in order to destroy evil forever in the resurrection.
- This merciful nature of God is revealed only in the good news of Jesus, in “the preached God.” Otherwise, God could well seem cruel or capricious. Jesus proves instead that He is “gracious and merciful, slow to anger and abounding in steadfast love” (Exodus 34:6).
- When bad things do happen, it does not mean God has abandoned us. Just the opposite, He promises that, in all situations, “My grace is sufficient for you.” (II Corinthians 12:9-10)