Albert Barnes Commentary Romans 2:15

"in that they show the work of the law written in their hearts, their conscience bearing witness therewith, and their thoughts one with another accusing or else excusing [them]);" — Romans 2:15 (ASV)

Which show. Who thus evince or show.

The work of the law. The design, purpose, or object which is intended by the revealed law; that is, to make known to man his duty, and to enforce the obligation to perform it. This does not mean, by any means, that they had all the knowledge which the law would impart, for then there would have been no need of a revelation; but that, as far as it went, as far as they had a knowledge of right and wrong, they coincided with the revealed will of God.

In other words, the will of God, whether made known by reason or revelation, will be the same so far as reason goes. The difference is that revelation goes farther than reason; it sheds light on new duties and doctrines. This is similar to how information from the naked eye and a telescope is the same, except that the telescope carries the sight forward and reveals new worlds to human vision.

Written in their hearts. The revealed law of God was written on tables of stone and then recorded in the books of the Old Testament. This law the Gentiles did not possess, but, to a certain extent, the same requirements were written on their hearts. Though not revealed to them as to the Jews, they had nevertheless obtained the knowledge of them by the light of nature.

The word hearts here denotes the mind itself, as it also frequently does in the sacred Scriptures—not the heart as the seat of the affections. It does not mean that they loved or even approved of the law, but that they had knowledge of it, and that knowledge was deeply engraved on their minds.

Their conscience. This word properly means the judgment of the mind respecting right and wrong, or the judgment that the mind passes on the morality or immorality of its own actions when it instantly approves or condemns them. It has usually been termed the moral sense and is a very important principle in a moral government. Its design is to serve the purposes of an ever-present witness to a person's conduct: to compel him to pronounce on his own doings, and thus to excite him to virtuous deeds, to give comfort and peace when he does right, and to deter from evil actions by making him, whether he wills it or not, his own executioner. (Acts 23:1; Acts 24:16; Romans 9:1; 1 Timothy 1:5).

By nature, every person thus approves or condemns his own acts; and there is not a more profound principle of the Divine administration than thus compelling every person to pronounce on the moral character of his own conduct. Conscience may be enlightened or unenlightened, and its use may be greatly perverted by false opinions. Its province is not to communicate any new truth; it is simply to express judgment and to impart pleasure or inflict pain for a person's own good or evil conduct. The apostle's argument does not require him to say that conscience revealed any truth, or any knowledge of duty, to the Gentiles, but that its actual exercise proved that they had a knowledge of the law of God. Thus it was a witness simply of that fact.

Bearing witness. To bear witness is to furnish testimony or proof. And the exercise of the conscience here showed or proved that they had a knowledge of the law. The expression does not mean that the exercise of their conscience bore witness of anything to them, but that its exercise may be alleged as proof that they were not without some knowledge of the law.

And their thoughts. The word thoughts (logismwn) means, properly, reasonings, or opinions, sentiments, etc. Its meaning here may be expressed by the word reflections. Their reflections on their own conduct would be attended with pain or pleasure. It differs from conscience, inasmuch as the decisions of conscience are instantaneous and without any process of reasoning. This supposes subsequent reflection, and it means that such reflections would only deepen and confirm the decisions of conscience.

The mean while. Margin, "Between themselves." The rendering in the margin is more in accordance with the Greek. The expression sometimes means in the meantime, or at the same time, and sometimes afterward, or subsequently. The Syriac and Latin Vulgate render this "mutually." They seem to have understood this as affirming that the heathen among themselves, by their writings, accused or acquitted one another.

Accusing. If the actions were evil.

Excusing. That is, if their actions were good.

One another. The margin renders this expression in connection with the adverb translated "in the mean while"—"between themselves." This view is also taken by many commentators, and this is its probable meaning. If so, it denotes the fact that in their reflections, or their reasonings or discussions, they accused each other of crime or acquitted one another; they showed that they had a law and that they acted on the supposition that they had. To show this was the design of the apostle, and no further proof of it was needed than what he here adduced.

1. They had a conscience, pronouncing on their own acts; and

2. Their reasonings, based on the supposition of some such common and acknowledged standard of accusing or acquitting, supposed the same thing. If, therefore, they condemned or acquitted themselves, if, in these reasonings and reflections, they proceeded on the principle that they had some rule of right and wrong, then the proposition of the apostle was made out that it was right for God to judge them and destroy them (Romans 2:8–12).