Read Revelation 16.
Have you ever wondered why people who are dying don’t just pray the “sinners prayer?” After all, if God will save everyone who calls on the name of the Lord, then someone could live a completely selfish, sinful life and be saved just before they reach eternity. So, why don’t more people do that?
One answer is that becoming a Christian is not just about praying some words, like a magic incantation. Receiving the gospel starts with changing your mind which is the act we know theologically as “repentance.” That change of mind requires a work of God in someoane’s heart which causes them to want God instead of sin. If you genuinely want God, you’ll turn to him as soon as you realize that you want him, not wait until the very end of your life. Although there are exceptions, the longer people live, the more hardened they usually become in their sin and rejection of Christ. To receive Christ is to renounce your pride, to admit that you’ve been living wrongly your whole life, and to fall on his grace alone because you’re unable to fix yourself or your situation. Apart from the grace of God, human pride keeps us from such repentance.
This is why the people described in today’s chapter “refused to repent and glorify him” (v. 9, and similar wording in verse 11). Instead of calling for God’s mercy, then, people cursed him for his justice (vv. 9, 11, 21). This is the natural response of humanity to the holiness, righteousness, and justice of God.
This is why we must pray for God to open hearts and change minds so that people will turn to God for grace instead of cursing him for his justice.