Charles Spurgeon 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 worketh wrath: for where no law is, there is no transgression (Romans 4:15).

That is plain enough. You cannot break a law if there is no law; and thus, through our sinfulness, the law becomes a cause of sin, and never does it become the cause of justification.