Scripture shows some ways in which God uses evil to further His purposes: to display divine grace and justice (Rom. 3:26; 5:8, 20-21; 9:17); to judge evil in the present and future (Matt. 23:35; John 5:14); to redeem through Christ's sufferings (1 Pet. 3:18); to expand gospel witness through the suffering of Christ's people (Col. 1:24); to shock unbelievers, get their attention, and call for a change of heart (Zech. 13:7-9; Luke 13:1-5; John 9); to discipline believers (Heb. 12:3-17); and to vindicate God (Rom. 3:26).
John MacArthur