Natural Marriage

In researching the subject of “homosexual marriage” I came across the concept of natural marriage. The idea, essentially, is that marriage precedes both religion and state (which is why the state cannot redefine it). This is analogous to natural law.

A hypothetical question arises: if a man and a woman were trapped on a deserted island with no immediate prospects of rescue would it be licit for them to form a natural marriage or would that be fornication? Let’s assume, for the sake of argument, that they are faithful both while they are on the island (might be an issue if there are others trapped with them) but also after being rescued and upon rescue that they formalize the marriage both civily and sacramentally.

What do you think?

Sort of, but not exactly.

Natural marriage is a valid marriage between two unbaptized people or between a baptized and non-baptized person.

Two baptized people who marry validly have a sacramental marriage, not a natural marriage. If they do not contract marriage validly, they have no marriage, not a natural marriage.

The church foresees circumstances in which a couple might not be able to exchange their vows before an official witness of the Church and makes provision for a valid marriage in such circumstance:

Can. 1116 §1. If a person competent to assist according to the norm of law cannot be present or approached without grave inconvenience, those who intend to enter into a true marriage can contract it validly and licitly before witnesses only:

1/ in danger of death;

2/ outside the danger of death provided that it is prudently foreseen that the situation will continue for a month.

§2. In either case, if some other priest or deacon who can be present is available, he must be called and be present at the celebration of the marriage together with the witnesses, without prejudice to the validity of the marriage before witnesses only.

FYI, In western Catholic theology, the minister of the Sacrament of Holy Matrimony are the bride and groom, who mutually confer it upon each other. (Eastern Catholics consider the minister to be the priest.)

A more interesting question is whether Adam and Eve were married in Eden - or was marriage a prudential necessity in a Fallen world?

I do not think marriage is necessitated by natural law.
But that depends how one understands natural law.

Not to be confused with a law of nature.
And do we consider Fallen nature or Eden nature.

Some say homosexual acts are a sin against nature while fornication is not.
That is true in one sense but not in the most important sense.

Actually ALL sin is against nature, including fornication.

Thanks, 1ke for that explanation and for the citation of canon law. I guess I should have known that the situation would have been anticiapted. (I’m curious now what examples there might be of it; my example was pretty contrived but the canon law is pretty broad and brings to mind the authority of a ship captain to solmenize marriage.)

As for Adam and Eve, I had thought about them. Setting aside their possible mythology, they are a very special case given their unique relationship with God. Not much is said about them in Genesis, do we even know if they had sex before the Fall (Eden nature)? But there is no formal marriage after the Fall so I think it’s fair to say that they had a natural marriage (Fallen nature).

This, I think, brings us to a more important question: the moral status of homosexual and fornication not to mention polygamy. My understanding is that both are “unnatural” in the Thomistic sense. (Obviously they are natural in the scienfic sense.) What this implies is that even without of before God’s revelation (and even for those who reject it), homosexuality and fornication are not the best expression of human sexuality and that this is something that one can arrive at by observation and reason.

What, then, are we to make of a society that is bent on legimitizing homosexual marriage, as it seems the US Supreme Court is about to do and which other nations including Pope Francis’ Argentina, have already done? It goes without saying that fornication has long since become normalized.

Are Catholics and the like exagerating the clarity of the natural law of human sexuality? Or has modern culture taken leave of it’s rationality including, particularly, the creame of society?

But if there is such a thing as natural marriage then what states, nations, and judges are doing is setting themselves against it. What happens when civil marriage diverges from natural marriage?

How is homosexual sexual activity natural in the scientific sense? Its not natural in any sense.

It is natural in the scientific sense that it can be observed in nature.

Conflating something being “natural” with it being “moral” is problematic. What would one argue is more “natural” - chastity and monogamy, or promiscuity?

Yes, the word “natural” has two distinct meanings. Unfortunately, the traditional moral meaning is no longer the commonly understood meaning. Most people interpret the phrase “homosexuality is unnatural” as representing the belief that it is not observed in nature.

My questions here about “natural marriage” are in regard to the Thomistic sense of the word “natural” which does incorporate morality. (

In this sense, chastity and monogamy are more natural (for human beings) than promiscuity because they are better aligned with the nature and purpose of human sexuality.

Actually in a certain (weak) sense polygamy is indeed natural according to Aquinas from memory.

Therefore one certainly couldn’t say polygamy is unnatural in quite same way that adultery is unnatural (in so far as it is sinful).
God could never make it lawful in the Old Covenant (for a time) if it were.

But as I say, if we do not understand that all sin is unnatural … then I doubt whether the word “unnatural” is being used in Aquinas’s primary use of that word.

This is an interesting point and well worth exploring here.

Here are some quick references for those, like Blue Horizon, who may need to refresh their memory or who, like me, had no idea what Thomas said on the subject of polygamy:

From the first, here are Thomas’ three tests:

  1. bringing forth and the education of children.

  2. the common life enjoyed by the spouses.

  3. sacramental sign given by the fidelity of one man to one woman.

Polygamy might seem to satisfy the first test if, as is usually the case, the husband is wealthy and can afford to raise all the children. However, this presumes that the education can be subcontracted out. To some extent that’s obviously true. But there is another sense in which it is not: it is well known that in modern society absent fathers are a major cause of social pathology. If, as commonly practiced, each wife may have her own home (or her own floor in a common home) forming, essentially, a distinct household, you have almost the equivalent of single mothers save for what time the father spends with that wife and family. If, on the other hand, the wives and children are combined then you have confusion over authority of the mothers. Multiple wives betting multiple children is not equivalent to one wife having very many children.

The same holds true for the second test. How close are a husband and wife likely to be if the wife is one of many? How common is their life, really? This is especially the case when, again as commonly practiced, the ages of the wives vary with new wives coming in as the other wives grow older with, often, the oldest wives becoming neglected.

Thomas notes that polygamy fails the third test but this is the least persuasive to me. Jesus did declare that marriage is one man and one woman but that begs the question why? It would seem arbitrary if polygamy fulfilled all other tests. Thomas notes that God had nothing ill to say about the polygamy of the patriarchs.

But I claim that Jesus opposed polygamy just as he opposed divorce, which also was permitted up until then and that he was, in this instance, teaching a tighter, more natural marriage. Of coures, if polygamy were truly unnatural then this ought to have been discovered without revelation and, indeed, polygamy remains exceptional outside of Christianity even where it is officially sanctioned because it has some serious problems.

Thanks BS, here is my precis of Aquinas’s actual words…

*Whatever renders an action improportionate to the end which nature intends to obtain…is said to be contrary to the natural law.
An action may be improportionate either to the principal or to the secondary end…

If it be in any way improportionate to the secondary end (or to the principal end, as rendering its attainment difficult or less satisfactory) it is not forbidden by the first precepts of the natural law.

But it is forbidden by secondary precepts derived from the first precepts of natural law.*

After some fairly thin prudential arguments (which you note) in this regard Aquinas concludes:
"It is therefore evident from what has been said that plurality of wives is in a way against the law of nature, and in a way not against it."

Obviously it is “good” enough to allow polygamy of his Chosen People (and indeed the Patriachs) for a time. Yet too imperfect for him to allow it when they came of aage spiritually.

And this is backed up by Aquinas who then goes on to say it was lawful for the Patriachs to enter into polygamy at that time:
Consequently a dispensation in this matter could be granted by God alone through an inward inspiration, vouchsafed originally to the holy patriarchs, and by their example continued to others.

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