viz. that those who have sinned under a law shall be condemned by it ; and vs. 14, 15, are the g-round of the assertion, that those who have sinned without a revelation shall yet be punished, because, though they have no law, they are a law unto themselves.
(14) For when the Gentiles, which have not the law, do hy nature the things of the law, &c. The word for does not indicate the connexion between this and the preceding verse, but between this and the first clause of the 12th, as just stated. 'The Gentiles are not excusable, although not amenable to the written law revealed to the Jews, since they have a law written upon their hearts, by which they shall be judged, and accord- ing to which they shall be punished.' In support of this assertion, the apostle appeals first to the moral acts of the heathen, as evincing a moral sense ; and secondly, v. 15, to the operations of their conscience. Do hy nature the things of the law. To do the things of the law is to do what the law prescribes. When they practise any of the virtues, or perform any moral acts, these acts are the evidence of a moral sense ; they show that the Gentiles have a rule of right and wrong, and a feeling of obligation, or, in other words, that they are a law unto themselves. The absence of all moral acts in the lower animals shows that they have no law or sense of moral obligation. But men, no matter how diversified may be their circumstances, all evince that they are under a moral law.
Paul says, the heathen " do hy nature the things of the law." The word rendered nature often signifies the natural constitution, innate tend- ency or disposition. This expression is common in all languages, and is used, as in this case by the apostle, to refer us to a source of acts independent of external causes and influences. When it is said that an animal is cruel by nature, it is meant that its cruelty is to be accounted for by its natural constitution, and not by imitation or example. When, therefore, the Gentiles are said ' to do by nature the things of the law,' it is meant that they have not been taught by others. It is neither by instruction nor example, but by their own innate sense of right and wrong, that they are directed. Having this natural sense of right and wrong, though destitute of a law externally revealed, they are a law unto themselves.
(15) Who show the work of the law written on their hearts, &c. The relative pronouns, when used in this way at the beginning of a clause, are often intended to introduce a reason for a preceding declaration. So here, the Gentiles are a law unto themselves, because they show the work of the law, &c. ; see ch. 1 : 25. 2 Cor. 8 : 10, &c. The expression work of the lavj may either mean the ' effect of the law,' viz. a knowledge of duty; or it may be a mere paraphrase for the law itself. Compare the somewhat similar expressions " work of the ministry," Eph. 4:12; " work of faith," 1 Thess. 1 : 3, though in neither of these cases is the word properly redundant. Paul says the Gentiles show that this law is written on their hearts by their actions, as stated in the previous verse.
There is another source of proof as to the existence of this internal law