Albert Barnes Commentary Romans 4:15

"for the law worketh wrath; but where there is no law, neither is there transgression." — Romans 4:15 (ASV)

Because the law. This refers to all law. It is the tendency of law.

Worketh wrath. This means it produces or causes wrath. While humanity is fallen and sinful, the law's tendency—far from justifying people and producing peace—is just the reverse. It condemns, denounces wrath, and produces suffering.

The word wrath here is to be understood in the sense of punishment (Romans 2:8), and the meaning is that the law of God, demanding perfect purity and denouncing every sin, condemns the sinner and consigns them to punishment. Since the apostle had proved in Romans 1:1-3:29 that all were sinners, it followed that if any attempted to be justified by the law, they would only be involved in condemnation and wrath.

For where no law is, etc. This is a general principle—a maxim of common justice and common sense. Law is a rule of conduct. If no such rule is given and known, there can be no crime. Law expresses what may be done and what may not be done. If there is no command to pursue a certain course, and no injunction to forbid certain conduct, actions will be innocent.

The connection in which this declaration is made here seems to imply that, as the Jews had a multitude of clear laws and the Gentiles had the laws of nature, there could be no hope of escape from the charge of their violation. Since human nature was depraved and people were prone to sin, the more just and reasonable the laws, the less hope there was of being justified by the law, and the more certainty there was that the law would produce wrath and condemnation.