The last section of Romans 1 describes what form the revelation of God’s wrath takes. Typically, we think of death and eternal damnation when we think of God’s wrath. These verses tell us that God pours out his wrath upon humanity prior to death and damnation. God not only gives them over to what their sinful hearts desire, he withdraws the grace that keeps the natural order of society from being turned on its head. Three sub-sections, each containing the phrase "God gave them up," describe this upending of the natural order and announce that it is due to the idolatry of futile thinking and darkened hearts. See these three sections beginning in verses 24, 26, and 28.
What does this action of "giving them up" accomplish as a function of his wrath prior to the final judgment?
First, this action results in a sort of hell-on-earth. Sin is destructive to humanity. It takes God’s good created order--the natural order that God built into his wonderful creation--and it turns it on its head. The upending of the natural order is a far cry from the ideal paradise that God originally created. As this world and the human condition gets farther away from the created order, it gets farther away from paradise and nearer to hell on earth.
Second, this action demonstrates the justice of humanity’s eventual judgment by showing sin to be exceedingly sinful and God to be exceedingly righteous. It heightens the contrast of the light against the dark. It displays the righteousness of God’s decree that those who practice and approve evil deserve to die. It stops every mouth, and holds the whole world accountable. It shows sin to be not merely sin, but sinful beyond measure. It allows God to be true and every man a liar.
Third, this action leaves humanity without hope in this world. No other god can save them. Nothing they have created and worshiped can give them hope. Sheer and utter hopelessness is the just judgment of God. No one who hates a righteous God deserves the hope of eternal life. God’s handing them over to their sin therefore guarantees their final judgment, in accordance with the will of their hearts.
This is a bleak section. But it serves to prepare us for the magnificent revelation of righteousness through the Gospel in the sections that follow. The contrast shows us how great are the mercies of God as he brings to pass his decree to reverse the curse, to restore creation, to turn the natural order right side up, and to give his loved ones the hope of glory.
There is light in the darkness.