John Calvin Commentary Leviticus 18

And the Lord spoke to Moses. I have not introduced this declaration among other similar ones, which aimed at preparing their minds for the reverent reception of the Law. This is because, whatever similarity there may be in the words themselves, in their substance, there is a great difference; for those declarations were general, while this one is specifically limited to a single point.

For it was not God’s intention here merely to urge the people to study the Law. Instead, the instruction concerning the keeping of His statutes is directed to the current issue. He does not refer without distinction to all His own statutes and those of the Gentiles, but restricts Himself to the specific subject matter. Therefore, by “the statutes of the Gentiles,” He means those corruptions by which they had perverted His pure institution of holy matrimony.

First, however, He forbids them from following the customs of the Egyptians, and then He includes all the Canaanite nations. For, since all Eastern peoples are lustful, they never had any hesitation in defiling themselves with incestuous marriages. Indeed, history clearly shows how great the excesses of the Egyptians ⁸⁶ were in this respect.

A brother felt no abhorrence of marrying his sister from the same mother, nor did an uncle feel any about marrying his niece, whether on his father's or mother's side. In short, they were so dead to shame that they were overcome by their lusts, trampling on all the laws of nature. This is the reason God here lists the kinds of incest, the mention of which would otherwise have been unnecessary.

Ye shall therefore keep my statutes. Although Moses introduces this passage, where he exhorts the Israelites to cultivate chastity concerning marriage and not to fall into the incestuous pollutions of the Gentiles, yet, as it is a remarkable one and contains general instruction from which Paul derives his definition of the righteousness of the Law (Romans 10:5), it seems to me to fit very appropriately here, since it sanctions and confirms the Law by the promise of reward.

The hope of eternal life is, therefore, given to all who keep the Law; for those who interpret the passage as referring to this earthly and transitory life are mistaken.¹⁹⁵ The cause of this error was their fear that in this way the righteousness of faith might be subverted, and salvation grounded on the merit of works.

But Scripture does not therefore deny that people are justified by works because the Law itself is imperfect, or because it does not give instructions for perfect righteousness; rather, it is because the promise is made ineffective by our corruption and sin.

Paul, therefore, as I have just said, when he teaches that righteousness is to be sought in the grace of Christ by faith (Romans 10:4), proves his statement with this argument: no one is justified who has not fulfilled what the Law commands.

Elsewhere he also reasons by contrast, where he contends that the Law does not harmonize with faith regarding the cause of justification. This is because the Law requires works for the attainment of salvation, while faith directs us to Christ, so that we may be delivered from the curse of the Law.

Foolishly, then, some reject as an absurdity the statement that if a person fulfills the Law, they attain to righteousness. For the defect does not arise from the doctrine of the Law, but from human weakness, as is clear from another testimony given by Paul (Romans 8:3).

We must observe, however, that salvation is not to be expected from the Law unless its precepts are complied with in every respect. For life is not promised to one who has done this thing or that thing; rather, the plural term used implies that full obedience is required of us.

The babblings of Papal theologians about partial righteousness are frivolous and silly, since God at once embraces all the commandments; and who is there that can boast of having thoroughly fulfilled them?

If, then, no one was ever clear of transgression, or ever will be—although God by no means deceives us—the promise nevertheless becomes ineffectual, because we do not perform our part of the agreement.

None of you shall approach anyone who is near of kin. This term does not include all female relations, for first cousins on the father’s or mother’s side are permitted to intermarry. Instead, it must be restricted to the degrees that He proceeds to enumerate and is merely a brief preface, declaring that there are certain degrees of relationship which render marriages incestuous.

We may, therefore, define these female blood relations as those spoken of immediately afterwards: namely, that a son should not marry his mother, nor a son-in-law his mother-in-law; nor a paternal or maternal uncle his niece, nor a grandfather his granddaughter, nor a brother his sister, nor a nephew his paternal or maternal aunt, or his uncle’s wife; nor a father-in-law his daughter-in-law, nor a brother-in-law his brother’s wife, nor a stepfather his stepdaughter.

The Roman laws accord with the rule prescribed by God, as if their authors had learned from Moses what was proper and agreeable to nature. The phrase God frequently uses, to uncover the turpitude, is intended to awaken abhorrence, so that the Israelites might be more diligent in guarding against all incest. The Hebrew word, indeed, ערוה, gnervah, signifies nakedness. Therefore, some translate it actively, “the nakedness of your father,” that is, the womb which your father has uncovered. However, this meaning would not be suitable for “the nakedness of your daughter,” or “your daughter-in-law,” or “your sister.” Consequently, there is no doubt that Moses means to indicate that it is a filthy and shameful thing.

We must remember, as I have already hinted, that not only are incestuous connections out of wedlock condemned, but also that the degrees are pointed out within which marriages are unlawful. It is true, indeed, that this was a part of the political constitution God established for His ancient people. Still, it must be kept in mind that whatever is prescribed here is deduced from the source of rectitude itself and from the natural feelings He implanted in us.

Absurd is the cleverness to which some people, little versed in Scripture, pretend,⁸⁷ who assert that since the Law has been abrogated, the obligations Moses laid on his countrymen are now dissolved. For it is to be inferred from the preface explained above that the instruction given here is not, and ought not to be considered, merely political. For, since their lusts had led astray all the neighboring nations into incest, God, to inculcate chastity among His people, says, I am the Lord your God; you shall therefore keep my statutes. Do not walk according to the practices of the land of Egypt, nor according to the practices of the land of Canaan. And then He adds what are the degrees of consanguinity and affinity within which the marriage of men and women is forbidden.

If any again object that what has been disobeyed in many countries is not to be accounted the law of the Gentiles, the reply is easy: namely, that the barbarism which prevailed in the East does not nullify the chastity that is opposed to the abominations of the Gentiles, since what is natural cannot be abrogated by any consent or custom. In short, the prohibition of incests set forth here is by no means among those laws commonly abrogated according to the circumstances of time and place, since it flows from the fountain of nature itself and is founded on the general principle of all laws, which is perpetual and inviolable.

Certainly, God declares that the custom which had prevailed among the heathen was displeasing to Him. And why is this, but because nature itself repudiates and abhors filthiness, even if approved by the consent (suffragiis) of men? Therefore, when God would by this distinction separate His chosen people from heathen nations, we may surely conclude that the incests He commands them to avoid are absolute pollutions.

Paul, on a very minor point, sets before our eyes the law of nature. For when he teaches that it is shameful and improper for women to appear in public without veils, he desires them to consider whether it would be decent for them to present themselves publicly with their heads shorn. And finally, he adds that nature itself does not permit it (1 Corinthians 11:14). Therefore, I do not see that, under the pretext of its being a political Law,⁸⁸ the purity of nature is to be abolished, from which arises the distinction between the statutes of God and the abuses of the Gentiles.

If this discipline were founded on the utility of a single people, or on the custom of a particular time, or on present necessity, or on any other circumstances, the laws deduced from it might be abrogated for new reasons, or their observance might be dispensed with for particular persons by special privilege. But since, in their enactment, the perpetual decency of nature was alone regarded, not even a dispensation of them would be permissible.

It may indeed be decreed that such actions should be lawful and unpunished, since it is in the power of princes to remit penalties. Yet no legislator can make a thing that nature pronounces vicious not be vicious; and if tyrannical arrogance dares to attempt it, the light of nature will soon shine forth and prevail. When, formerly, the Emperor Claudius had married his niece Agrippina,⁸⁹ to avert the shame, he procured a Senatusconsultum which licensed such marriages; yet no one was found to imitate his example, except one freedman.

Hence, just and reasonable men will acknowledge that, even among heathen nations, this Law was considered indissoluble, as if implanted and engraved on the hearts of men. On this ground Paul, to reprove more severely the incest of a stepson with his father’s wife, says that such an occurrence is not so much as named among the Gentiles (1 Corinthians 5:1).

If it is objected that such marriages are not prohibited to us in the New Testament, I reply that the marriage of a father with his daughter is not forbidden there, nor is a mother prohibited from marrying her son. Shall it therefore be lawful for those who are near of kin to form promiscuous connections?⁹⁰ Although Paul expressly mentions only one kind of incest, he yet establishes its disgrace by citing the example of the Gentiles, so that we at least should be ashamed if more delicacy and chastity is seen among them. And, in fact, another admonition of the same Paul is enough for me, who thus writes to the Philippians:

Whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things (Philippians 4:8).

As to those who ascend or descend in a direct line, it sufficiently appears that there is a monstrous indecency in the connection of father and daughter, or mother and son. A licentious poet,⁹¹ being about to relate the frantic incest of Myrrha, says:

“Daughters and fathers, from my song retire,
I sing of horror.”

In the collateral line, the uncles on both sides represent the father, and the aunts the mother. Consequently, connection with them is forbidden, inasmuch as it would be of somewhat similar impropriety. The same rule affects affinity: for the stepmother, or mother-in-law, is held to stand in the relation of mother; and the stepdaughter, or daughter-in-law, in that of daughter. Likewise, the wife of the paternal or maternal uncle is to be regarded in the relation of mother.

And, although express mention may not be made of it here, we must form our judgment by analogy as to what is prohibited. For example, the uncle on the father’s or mother’s side is not explicitly forbidden here to marry his niece. However, since the nephew is interdicted from marrying his paternal or maternal aunt, the mutual relation of the inferior to the superior degree must prevail. But if anyone should contend that there is a difference, the reason Moses adds refutes his objection, for it is said, She is your father’s or your mother’s near kinswoman. Hence it follows that a niece is guilty of incest if she marries her uncle on either side.

As to brothers and sisters, God pronounces that marriage with a sister, even if she is not uterine, is unlawful. For He forbids the uncovering of the turpitude of a sister, who is either the daughter of your father or the daughter of your mother.

You shall not uncover the nakedness of your brother’s wife.⁹² They are bad interpreters who raise a controversy on this passage and interpret it to mean that a brother’s wife must not be taken from his bed, or, if she is divorced, that marriage with her would be unlawful while her husband was still alive. For it is inconsistent to twist declarations made in the same place and with the same words into different meanings.

God forbids the uncovering of the turpitude of the wife of a father, an uncle, and a son. When He lays down the same rule regarding a brother’s wife in the very same words, it is absurd to invent a different meaning for them. Therefore, if it is not lawful to marry the wife of a father, a son, an uncle, or a nephew, we must hold precisely the same opinion regarding a brother’s wife, concerning whom an exactly similar law is enacted in the same passage and context.

I am not, however, ignorant of the source from where those who think otherwise have derived their mistake. For since God gives a command in another place that if a man has died without issue, his surviving brother shall take his widow as his wife, so that he may raise up seed from her for the departed (Deuteronomy 25:5), they have incorrectly and ignorantly restricted this to own-brothers, although God actually designates other degrees of relationship. It is a well-known Hebrew idiom to include all near kinsmen in general under the term "brother"; and the Latins also formerly called first cousins by this name.⁹³

The law we are now considering, then, regarding marriage with a deceased brother’s wife, is only addressed to those relatives who are not otherwise prohibited from such a marriage, since it was not God’s purpose to prevent the loss of a deceased person’s name by permitting those incestuous marriages, which He had elsewhere condemned. Therefore, these two points agree perfectly well: an own-brother was prohibited from marrying his brother’s widow, while the next of kin were obliged to raise up seed for the dead, by the right of their relationship, wherever their marriage was otherwise permissible by the enactments of the law.

On this ground, Boaz married Ruth, who had previously been married to his near kinsman; and it is abundantly clear from the history that the law applied to all the near kinsmen.

But if anyone still contends that own-brothers were included in the number of these, then on the same grounds the daughter-in-law would have to be married by her father-in-law, the nephew’s wife by the uncle, and even the mother-in-law by the son-in-law—which is an abomination even to speak of.

If anyone objects that Er, Onan, and Shelah, the sons of Judah, were own-brothers, and yet Tamar married two of them, the difficulty is easily solved: namely, that Judah, following the common and accepted practice of the Gentiles, acted improperly in permitting it. It is plain enough from the histories of all ages that there were disgusting and shameless mixtures in the marriages of Oriental nations. By evil communications, then, as is always the case, Judah was led into giving the same wife to his second son who had previously been married to the eldest. And, in fact, God expressly says that this offense was widespread among the Gentiles, where He condemns incestuous connections.

This, therefore, I still hold to be unquestionable: that by the law of Moses, marriage with the widow of an own-brother is forbidden.