In the last few days, several have commented on various religious/cultural practices regarding forms of marriage and the justification of such. In reality, different practices evolve according to 1)needs (imbalance of the sexes, etc.), 2) the examples of the rich and powerful (usually male) who choose a lifestyle to suit personal wishes.3) various stories and rules set out in religious texts. (perhaps there are 4). 5)....but these will do to make my point. (forgive my seeming tedious formality, but I'm trying to phrase this as neutrally as possible)
   When precedent is set due to #1 & #2, the stories of #3, edited and repeated and embroidered and interpreted can create a powerful incentive to behave AS IF they are true & binding, whether they are totally factual or not.
Jesus may or may not have some basis in fact.... he may have been one person, or a conglomerate of several persons whose stories were mixed...or even mostly stories/legends based loosely on some actual person or set of persons.(Mohammed seems to have a bit more documentation, but the details are still debated among Muslim scholars) What we are dealing with is how people accept, internalize and follow various stories..(again-whether they are true, partially true, or largely invented.)

Children 'believe' in all sorts of things when they are very young. They even treat cartoon characters with serious attention and 'worry' about their situations. Santa Claus & the Easter Bunny and the Tooth Fairy are usually abandoned by age 6-10 as they see the logic of it all and as adults break the news formally. But when adults continue to repeat some stories as not only actual, but important & binding, these stories are often internalized until they are part of the fabric of living.... again, whether they are true or not!.
It is not even necessary to BE a child to be susceptible to well-told stories and ideas... politicians and missionaries know this well..... but children are especially vulnerable.

If you care to read about one example, see this article about Slender Man, a fictional entity created only a few years ago, but which affected some young minds in very frightening ways.

We can debate interpretations of scriptures and the habits of various cultures forever... but, in my opinion, no discussion of polygamy-Bigamy laws is complete without considering... implicity, if not explicitly, the ways in which we learn and process these mindsets. Even debating them only from a practical viewpoint ..(can regulations BE written that would fairly and clearly cover all the possibilities)... is, as we above, quite awkward.

The only answer that I can see is to not be hasty to judge and to allow others to follow their own path as long as it doesn't compromise MY path............and of course, off we go again about perceived compromising of paths.

(side note... I firmly believe that one reason so many just choose one opinion and cling to it, is that very few care to deal with the long, tedious explications that we philosophical types indulge in... ;>) )