Romans 1:18—God reveals his wrath against the ungodly and unrighteous.

This verse begins Paul’s systematic indictment of human rebellion against God. In two sections extending all the way to 3:20, Paul addresses first primarily Gentile idolatry and then Jews who think they can be justified by law keeping. His conclusion comes at 3:9: “all, both Jews and Greeks, are under sin.”

Gentiles are found guilty for ignoring God’s revelation of himself in nature, and Jews for failure to meet the standards set forth in God’s revelation of himself in Scripture. Paul’s focus in this section, then, is on why the gospel is necessary, before returning to the gospel’s details in 3:21. As Douglas Moo points out, Paul implicitly acknowledges that 1:18–3:20 interrupts his exposition of the righteousness of God by restating 1:17 in 3:21: “But now the righteousness of God has been manifested.”

The wrath of God
Just as God reveals his righteousness (verse 17) so he reveals his wrath. The Greek word (orgē) means violent passion, ire, or abhorrence (Strong’s lexicon). Divine wrath is a necessity if God is truly righteous, because he cannot tolerate that which is opposed to his character. Divine love, too, requires divine wrath. “A God of love must hate anything that harms those He loves,” states Charles Swindoll. “A God of love must take action to protect the innocent against the malicious.”

This is why people who complain about God’s wrath, if they are logical, would also have to object to human indignation against evil. Charles Cranfield writes, “A man who knows, for example, about the injustice and cruelty of apartheid and is not angry at such wickedness cannot be a thoroughly good man; for his lack of wrath means a failure to care for his fellow man, a failure to love.”

Present and future wrath
The present tense—“is being revealed”—suggests God is already manifesting his wrath, perhaps by intensifying through his sovereign action the natural consequence of sin in the lives of those who reject the gospel. J. I. Packer observes that the transfer of reverence from God to idols “leads to drastic moral decline, with consequent misery, as a first manifestation of God’s wrath against human apostasy.”

Every human being apart from Christ is already under God’s wrath. In Jesus’ own words, “Whoever believes in the Son has eternal life; whoever does not obey the Son shall not see life, but the wrath of God remains on him” (John 3:36).

The full impact of divine wrath is yet to be revealed (2:5), and the only escape from that wrath is through God’s gospel. The connective “For” at the beginning of the verse points back to faith in that gospel as the means to acquire the gift of God’s righteousness (verses 16–17). In this sense the gospel reveals both the righteousness of God and the dire warning implicit in God’s wrath.

Ungodliness and unrighteousness
Ungodliness is lack of reverence for God, and unrighteousness conveys unjust behavior toward people. The second term is a consequence of the first: “The basis of ethical conduct rests on the nature of God and our attitude toward him, otherwise the law of the jungle” (Archibald Robertson). Both terms together, then, sum up the totality of humanity’s sin toward God and one another.

Suppress the truth
Specifically, it is by unrighteousness that people suppress the truth. Note that, according to Paul, the response to biblical truth requires more than mental assent. Truth is to be obeyed. As Robert Utley says, Paul means “(1) they know the truth but reject it; (2) their lifestyle shows they reject the truth; or (3) their lives and/or words cause others not to know and receive the truth.”

Robertson points out that the Greek word for truth (alētheia) means the opposite of concealment. So truth, he says, “is out in the open, but wicked men, so to speak, put it in a box and sit on the lid and ‘hold it down in unrighteousness’.” Everett Harrison quotes R.C.H. Lenski:

God, who sees every aspect of our lives, is not fooled. His warning to a dying world comes directly “from heaven.” And heaven also shouts to earth the way of escape that was conceived in heaven and made possible by God’s Son taking on himself the wrath we deserved (2 Corinthians 5:21). The gospel declares that by Christ’s death and resurrection he gave us, on the basis of faith in him, God’s righteousness instead of wrath, having purchased our peace with God (5:1).