Saturday, July 27, 2019

The Trinity, sexual ethics and liberal Christianity

Many Christians deny traditional Christian doctrines regarding sexual ethics while accepting traditional Christian Trinitarian doctrine. This seems to me to be a rationally suspect combination because:

  1. The arguments against traditional Christian sexual ethics are weaker than the arguments against the doctrine of the Trinity.

  2. A number of the controversial parts of traditional Christian sexual ethics are grounded
    at least as well in Tradition and Scripture as the doctrine of the Trinity is.

Let me offer some backing for claims 1 and 2.

The strongest arguments against traditional Christian sexual ethics are primarily critiques of the arguments for traditional Christian sexual ethics (such as the arguments from the natural law tradition). As such, these arguments do not establish the falsity of traditional Christian sexual ethics, but at best show that it has a weak philosophical foundation. On the other hand, the best arguments against the doctrine of the Trinity come very close to showing that the doctrine of the Trinity taken on its own terms is logically contradictory. The typical Christian theologian is the one who is on the defensive here, offering ways to resolve the apparent contradiction rather than giving rational arguments for the truth of the doctrine.

There are, admittedly, some arguments against traditional Christian sexual ethics on the basis of intuitions widely shared in our society. But we know that these intuitions are very much shaped by a changing culture, insofar as prior to the 20th century, one could run intuition-based arguments for opposite conclusions. Hence, we should not consider the arguments based on current social intuitions to be particularly strong.
But the intuition that there is something contradictory about the doctrine of the Trinity does not seem to be as dependent on changing social intuitions. The merely socially counterintuitive is rationally preferable to the apparently contradictory.

Neither the whole of the doctrine of the Trinity nor the whole of traditional Christian sexual ethics is explicit in Scripture. But particularly controversial portions of each are explicit in Scripture: the Prologue of John tells us that Christ is God, while both Mark and Luke tell us that remarriage after divorce is a form of adultery, and Paul is clear on the wrongfulness of same-sex sexual activity. And the early Christian tradition is at least as clear, and probably more so, sexual ethics as on the doctrine of the Trinity.

I am not saying, of course, that it is not rational accept the doctrine of the Trinity. I think the arguments against the doctrine have successful responses. All I am saying is that traditional Christian sexual ethics fares (even) better.


Walter Van den Acker said...


You are comparing absolutely mysterious notions like the Trinity with much more mundane issues like sexual morality. Most Christians I know really have no clue what the doctrine of the Trinity entails. My mother e.g., who is a devout Catholic, does not really care about the Trinity, partly because it has no direct impact on her life but also because understanding the Trinity requires a kind of theological background that she (and most other Catholics) simply doesn't have. She doesn't know that there are (strong) arguments against the Trinity. She has, however, heard lots of (strong) arguments for and against traditional Christian sexual ethics.

BTW, both Luke and Mark talk about a husband divorcing his wife or a wife divorcing her husband. I don't see anything about a divorce with mutual consent.

Alexander R Pruss said...

1. The doctrine of the Trinity should be central to a Christian's devotional life. That is why the sign of the cross, with its Trinitarian wording, is the central Catholic prayer.

2. Good point about divorce: that is indeed a slight complication. Note, however, that Luke and Mark talk of remarriage after divorce as a form of adultery (presumably because the first marriage is still really in place, no matter what the law may say). And adultery doesn't become permissible just because someone's spouse's consents to it.

Walter Van den Acker said...


It may be that the doctrine of the Trinity should be central to a Christian's devotional life and it may be that the doctrines regarding esxual ethics should also be important for a Christian, but that's not the point.
The point is that understanding an abstract theological concept like the doctrine of the Trinity (and consequently the arguments against it) is probably much harder than understanding the doctrine of sexual ethics (and arguments against it).

As to what Luke and Mark have to say about remarriage, I think that is too ambiguous to draw too many conclusions. I don't think, e.g. that it is so obvious that if someone's spouse really agrees to it, we can speak of adultery at all. One of the problems is, I think, that in Luke and Mark's days, the female partner didn't really have a say in this matter.

Red said...

Isn't it obvious that that what is known as logical problem of trinity is much more intractable and easier to grasp then why certain moral principle contained in the scripture is false?

It seems it is easier to understand "How three can be one?" than "Why is certain ethical principle wrong?"

Walter Van den Acker said...


I think what Alex is saying is that arguments against the Trinity are stronger that arguments against traditional sexual morality.
I actually agree with this. Although I think that there are compelling arguments against traditional Christian sexual ethics, they are not as straight-forward as arguments against the Trinity. The Trinity to me is simply a logical contradiction.
But, as I told Alex, most ordinary Christians do not really care about the Trinity (although perhaps they "should") and do not understand the subtleties of the doctrine of the Trinity.
They probaly don't understand the subtleties of natural theology either and that's why they probably think the arguments against traditional sexual ethics are stronger, or at least strong enough.

Michael Gonzalez said...

I won't go into the Trinity, unless someone really wants me to (paraphrase: it is not only a self-contradiction, but also contradicts many many Scriptures; necessitating a second look at the only favorable text, John 1:1, in which the Logos is actually called "god", not "God"... no definite article... anyway....).

I want to quickly address the re-marriage thing, and then get to Pruss' actual point (since the specific examples aren't really the point): Matthew's account gives the missing detail from Mark and Luke (this is why there are 4 Gospels), namely that divorce is only permitted if sexual immorality (Greek: porneia) has been committed. If it hasn't, then the marriage is still intact in God's eyes, and so marrying another is committing adultery. But, again, the specific example of remarriage isn't the point.

To Pruss' main point: I very much agree that professed Christians seem much more willing to accept the seemingly contradictory than the "out-of-date" and socially/morally restrictive. Whether the Trinity is true, or how it could be true, are regarded as intellectual puzzles at best. But, whether homosexual unions are wrong in God's eyes is a very practical, real-life issue for many. This is an obvious case of people living inconsistently with their worldview.

Alexander R Pruss said...


Mark and Luke say, without exception, that remarriage after divorce is adultery. If we take seriously the idea that each Gospel is divinely inspired, then that has to be true, and the Matthew "exception" has to be understood as consistent with that. How could that be? I think the only possibility is that it's one of those "exceptions" that isn't really an exception.

Imagine a sign on a lane that says: "Motorcycles not permitted, ebikes excepted." Ebikes aren't motorcycles (at least according to the definitions in many jurisdictions). The sign could have just said "Motorcycles not permitted", but of the sake of clarity it emphasizes that ebikes are OK.

In other words, if all three Gospels are divinely inspired, Matthew is excepting a case which isn't actually a case of divorce. What could that case be? Well, the Matthew text is ambiguous as to where the porneia occurs: does it occur (a) between one of the parties in the "divorce" and a third party or (b) between the two parties in the "divorce". If the answer is (a), then we have a contradiction to Mark and Luke. So, I say that the answer is (b): namely, the "exception" is talking of cases where the couple has a marriage-like relationship but that marriage-like relationship is actually a case of sexual immorality (=porneia) rather than of a real marriage.

This is not at all far-fetched. For instance, the couple could be too closely related by blood for marriage, and hence their relationship could be incest, a form of sexual immorality or porneia. In that case a "divorce" would not only be permitted, but required. One Bible I have says in a footnote that this wouldn't have been an uncommon issue to deal with among gentile converts. A more common example in our time is where we have three Christians, A, B and C, where A was married to B, A divorced B and A "married" C. Then the relationship between A and C constitutes adultery (against B), and adultery is a form of porneia. In such a case, "divorce" between A and C would be permitted, indeed required.

Michael Gonzalez said...

Pruss: A couple of concerns on the remarriage issue:

1) Jesus adds the "except on grounds of [porneia]" caveat both in the Sermon on the Mount and also on a separate occasion (Matt. 5:32 and 19:9); it just happens to be only Matthew who recorded it. Could his statements recorded by Mark and Luke not be understood in the light of Matthew (some traditions have his Gospel as having been written first, after all; as early as 41CE, for that matter)?

2) One very straightforward way to read all three harmoniously is that legal divorces do not end marriage in God's eyes at all; and so a mere legal divorce leaves one able to commit adultery, since they are still married in God's eyes. However, sexual immorality + divorce severs the bond even in God's eyes, and then a person would not commit adultery if they remarry. After all, death severs the bond, and the widow(er) is indeed permitted to remarry without committing adultery. So, there is no conceptual barrier to dissolution of a marriage and being free to remarry in general.

3) 1 Corinthians 6:16-18 says that a person who commits fornication becomes "one flesh" with the other party and sins against his own body. (As such, if he is married, he sins against the one with whom he had been "one flesh" up to that point.) This furnishes a logical framework for dissolution of the marriage bond in God's eyes by adultery. Here's how the reasoning would go: The guilty spouse has become "one flesh" with a new party, and therefore is not "one flesh" with the innocent spouse anymore. Now, the innocent spouse could choose to forgive and to resume the full marriage with the guilty one, at which point they would again be "one flesh" together, and she would no long have grounds in God's eyes to divorce and remarry. But, if she chooses not to forgive, and divorces him while he is "one flesh" with the other guilty partner, it seems clear that she would now be free to remarry and become "one flesh" with another.

4) The Law of Moses sheds light on God's thinking (e.g. Exodus 21:22-25 is often cited to elucidate God's view of abortion). From that Law: Deuteronomy 24:1-4 says that a divorced woman may become another man's wife (clearly without committing adultery, which would have been a capital offense); with the only caveat being that she could never re-marry the original husband. Interestingly, the sins covered under "porneia" would be have resulted in the death of the original mate anyway, and death obviously frees her to remarry.

Sorry if this derails the main point, but I thought it deserved a bit of discussion (especially if a ban on remarriage simpliciter is included in the "Biblical morality" that we expect people to adopt and follow).

Alexander R Pruss said...

Ad 2: That still makes Mark and Luke not be quite true: It is not true that "ANYONE who divorces his wife and marries another commits adultery against her." It is only true that "Anyone who divorces his wife without prior adultery and marries another commits adultery against her." That said, I have to admit that on my own reading there is some quantifier restriction, too, because I think this only applies to Christians.

Ad 4: The disciples are clearly horrified by Jesus's teaching in Matthew 19, since they say that if so, it's better not to marry. This suggests that they see his teaching as more extreme than the predominant rabbinical views of the time. There were two predominant rabbinical views here: (1) divorce is permitted only after adultery (Shammai school) and (2) divorce is permitted much more broadly (Hillel school). (Or so I've heard. Not my primary area of scholarship.) So if Jesus had the view that allowed divorce and remarriage after adultery, his view would not be very surprising: it would have just been the Shammai view. The inclusion in the Sermon on the Mount makes it likely that Jesus is being quite a bit more radical than the rabbinical schools, since Jesus generally is very radical in the Sermon on the Mount.