The purpose of a rhetorical interrogative is to so phrase a question that its answer is obvious to all. As has been his custom in Romans, Paul through his inspired pen not only asks two more rhetorical questions in chapter seven, he emphatically answers them so there can be no doubt.
“Is the Law sin? Certainly not!” (v. 7). “Has then what is good become death to me? Certainly not!” (v. 13).
Because of his own back story and his extensive religious discussions with the Jews in the synagogues of Asia and Europe (Acts 14:1; 17:2; 18:4, 19; 19:8), the apostle Paul was quite familiar with the biggest objections a conscientious Jew had to leaving the Law of Moses and embracing the gospel of Jesus Christ.
Such a conversion in one’s thinking is most challenging but absolutely necessary.
When asked sincerely, the two rhetorical questions above are legitimate and appear—on the surface—to be unanswerable. But, such is not true.
The Law of Moses is not sin (v. 7), nor is it a source or agent of sin and death (v. 13). Such thinking is misguided because it overlooks a most integral piece of the overall picture—Satan. The Law of Moses (or “Torah”, i.e. “instruction” or “teaching”) was given to supply essential spiritual knowledge on such things as godliness and ungodliness, righteousness and unrighteousness, plus holiness and unholiness. For this reason, it is holy, just, and good (v. 12).
This truth about the Law logically—and therefore, legitimately—leads to the puzzle of: “Has then the Law which is good become death to me?” And, again, this is “Certainly NOT!” true. Satan has produced death via his vicious and deadly tool of sin. God and His Law are not in any way culpable for humanity’s sin and the death it generates.
When it comes to sin—all human ungodliness and unrighteousness—the devil seduced me into doing it is always the truth on the matter.