PREMISE

My basic understanding is that spiritual marriage is not created when two people sign a piece of paper and file it with the courthouse. It's also not created when a pastor/priest says, "I now pronounce you ..." Adam and Eve didn't have these things, nor did their children. These are man-made conventions to publicize and officialize a covenant that was already otherwise created.

How was it created? By two flesh becoming one. In my view, this alone creates a marriage. The one possible exception is rape, so I'll often suggest that the act of becoming one flesh (i.e. having sex) must also be mutual/consensual. But the Bible also says that if a man raped a woman he was obligated to marry her (Deuteronomy 22:28-29). So, maybe even rape is considered to create a one-flesh marriage bond - I don't take a strong position on that. The exception here is, of course, that a daughter was considered at the time to be the property of her father, and her father (per Exodus 22:16-17) could refuse to give his daughter to a man who she had sex with, without ever having gone through a marriage ceremony.

In short, sex = marriage, even if there is no ceremony. Although I use the phrase somewhat flippantly, because of this view I really don't believe "premarital sex" is a thing. Instead, I would technically call it "pre-ceremony sex."

IMPLICATIONS

An Example

So, if a guy goes out and has "pre-ceremony sex" as part of a one night stand, I would see that as creating a spiritual bond of marriage between the two of them. The initial act itself is not sinful. It only becomes sin when he then abandons that relationship for another one, in which case his new partner is now someone with whom he is in an adulterous relationship. Of course, this only applies if you believe monogamy was God's only intent and that God always condemns polygamy as sinful, but just never specifically said it.

Alternatively, if you don't believe polygamy is inherently sinful (rather it's only sinful if your government condemns it, by virtue of Romans 13 and similar passages, which is the case in America), you could view the new partner as a polygamous relationship and say that the man is not in sin for now having married someone else. It is spiritually lawful polygamy. Instead, the sin is that he's not maintaining the God-given obligation to the first girl from the ONS. He has failed his first wife, despite being faithful to his second.

Polyandry

The sin compounds, then, if she goes off and sleeps with another guy. Why? Because tacit approval of polygamy in the Bible (i.e. the fact that God never condemned it and at times seems to endorse it) was only ever one-directional. Polyandry never got similar attention.

Would polyandry have received similar tacit approval from God if it was culturally common enough to be worth addressing? I don't know, but I'd wager not. If we look at the relationship with God and the Church, it still seems one-directional. Christ has one bride: his Church. Sure. But that church has many people. I am Christ's bride just as much as my pastor is, just as much as my wife is, etc. But ... if I, as Christ's bride, decide to go take for myself a second husband (i.e. marry myself to another god), that's a violation of Rule #1: "Thou shalt have no other gods" ... unless of course you want to argue that "no other gods before me" means you can have other gods as long as YHWH is your highest god - a position I would obviously reject based on other passages.

THE QUESTIONS

Now, all of this obviously seems ... off. But it's also the most Scripturally consistent understanding I can come up with of how marriage itself actually functions under a biblical model. So, am I missing something in the Bible here, or are all of our views on "biblical marriage" really just cultural views that "seem right to a man" (see where Proverbs 14:12 takes that), so we assume God meant to say that and just forgot to spell it out clearly enough?

What rubric do you use to discern if your views on marriage, premarital sex, extramarital affairs, polygamy/polyandry, etc. are based on cultural influences or Scripture alone? For Catholics, this is obviously different. Tradition has authority. Although polygamy has a rich tradition as well, I suppose decrees from church leaders can override the history of polygamy among God's people? Or am I misunderstanding that?

For those that do believe that a legal marriage certificate is necessary to create a marriage bond, where's the biblical basis for that? What if a government decided to change its laws to say that only homosexuals may get marriage certificates. Would you then argue that a Christian could not possibly get married in that country? (implications aside, of course, on whether or not homosexuals trying to get married can be rightly called Christians - a conversation held ad nauseam elsewhere).

DISCLAIMER: I have no intention of entering into a polygamous marriage, having an affair, or encouraging anyone toward pre-ceremony sex. Even if that sex is not sinful, waiting until there's a ceremony still has value in causing people to wise-up about what exactly they're doing when they create a marriage bond. I'm more just looking for feedback on a possible model for understanding marriage dynamics in the Bible.