God’s wrath is necessary because wrath is an attribute of His, that due to His Holy, Sanctified hatred for sin, must judge those who practice it. By His very nature He cannot tolerate evil. He hates it! It cannot be in His presence – (Habakkuk 1:13a) (Psalm 5:1-6) (Psalm 11:5) (1 John 1:5). God would not be God if He did not punish evil. Note this “God’s wrath is the beginning of the gospel”Without the reality of God’s wrath coming upon sinful men there is no gospel (good news). (Romans 6:23)….For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord.
Look now at another key explanation of the gospel (Romans 5:8-9). Listen, we can never understand the depth of God’s mercy, the necessity of the cross – unless we first understand God will avenge wickedness with His wrath. We cannot have the slightest idea of what Jesus did on the cross unless we see that God cannot and will not tolerate sin in His presence. Without His mercy we are all subject to His judgment! We should be deeply humbled by His choice to make us vessels of mercy (Romans 9:14-26).