This is because no human being can be considered right with God by [obeying] the requirements of a law. [Note: It is difficult to determine the exact sense in which "law" is used in these verses. It may be law generally, or the law of Moses specifically. See Bruce, pages 52-58]. For the knowledge of what sin is comes from the law of Moses.

For all those people [i.e., Gentiles] who have sinned without [knowing] the law of Moses will also be lost without [knowing] that law. And all those people [i.e., Jews] who have sinned under [the authority] of the law of Moses will be judged by [the requirements of] that law.

Or, do you not know, brothers, (I am talking to people who know how law works) that the law has authority over a person only as long as he lives? [Note: It is not clear whether this refers to Roman law or the law of Moses].

Now the practice of circumcision [i.e., the Jewish rite of identity, signifying the responsibility to observe the law of Moses] is worthwhile, providing you obey [the rest of] the law of Moses. But if you disobey the law, you might as well have never been circumcised.

Now we [all] know that everything the law says applies to those who are under [obligation to obey] that law, [Note: Here "the law" appears to refer to the Old Testament Scriptures generally, since Psalms and Isaiah are quoted. See verses 10-18]. This is so that the mouth of every objector may be stopped [i.e., from making excuses for his sin], and thereby bring the entire world under God's judgment [i.e., both Jews and Gentiles].

What shall we say then? Is the law of Moses sinful? Certainly not! For I would not have known what sin was if it had not been for the law. For [example]; I would not have known [what it meant] to covet [i.e., have a strong desire for what belongs to someone else] except that the law said [Ex. 20:17], "You must not covet."

but I see a different law [at work] in my body, waging [spiritual] warfare against the law in my mind. It brings me into captivity to the law of sin in my body.

For [it is] not those who hear the law of Moses who are right with God, but [it is] those who obey [the requirements of] that law [perfectly] who will be considered right with God.

(For when the [unconverted] Gentiles, who do not have the law of Moses, instinctively practice [some of] its requirements, they become their own lawmakers, even though they do not have the law of Moses.

You boast about having the law of Moses, [but] do you dishonor God by breaking that law?

So, will not those physically uncircumcised people [i.e., the Gentiles], who obey the law, condemn you [Jews] for breaking the law, even though you have the written code and [practice] circumcision?

But now [i.e., under the Gospel age], a way of being considered right with God apart from [any] law has been made known. [The writings of] the law [i.e., the Pentateuch] and the prophets bear witness to this.

Where then is the [basis for] boasting [i.e., over being right with God]? There is not any. Is it by [obedience to] a law? Is it by doing certain deeds? Not at all, but by a law of faith.

For we conclude that a person is made right with God by faith [in Christ], apart from [obedience to] the requirements of a law [or, the law of Moses, See verse 20].

Do we then [intend to] destroy law [observance] because faith [in Christ is now required]? Certainly not! But [instead], we uphold [the validity of] law.

For the law brings [God's] wrath [i.e., because of man's failure to obey it perfectly], but where there is no law, there is no [responsibility for] sin.

For even before the law of Moses, sin was [being committed] in the world. But man is not responsible for [his] sin when there is no law.