The issues of Marriage and Family particularly pop up repeatedly. The issue of polygamy (BOY that's a ripe pun...) or specifically Biblical polygyny keeps being flogged in the Virtual Debates.
Beyond the obvious (apparent) attraction of being able to do more than one woman ethically (tho' not simultaneously- threesomes are frowned upon in much "Biblical" polygynous ettiquette) I cannot fathom the attraction. There is the putative Biblicality of it all (David, Solomon...like that), but having lived in a two-nuclear-family household for a time (no hanky-panky there) having two ummm, strong willed women under the same roof was a trial at best.
Perhaps separate tents would have been the answer.
Most of the proof of God's happiness with the arrangement is circumstantial.
David was King, and a man after God's own heart.
David had multiple wives.
Therefore God wants men to have multiple wives.
Solomon had multiple wives.
God blessed Solomon.
Therefore God was happy with Solomon's multiple wives.
Not good syllogisms, no, but the reasoning tends to run that way.
God did not condemn it, therefore He is happy with the arrangement.
When God states a thing, he does NOT have to repeat it. Once "Thou shalt not steal" is chiseled into stone, well, He has published it. He does not therefore have to go to each man-jack of us in serial theophanies and say "Y'all don't be five-finger-discountin' at the Wal-Mart, y'hear?".
The most basic Scripture on marriage is this:
So the LORD God caused the man to fall into a deep sleep; and while he was sleeping, he took one of the man's ribs and closed up the place with flesh. 22 Then the LORD God made a woman from the rib he had taken out of the man, and he brought her to the man.
23 The man said,
"This is now bone of my bones
and flesh of my flesh;
she shall be called 'woman, '
for she was taken out of man."
24 For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh. (Gen.2)
Jesus went on to quote this in Matthew:
4"Haven't you read," he replied, "that at the beginning the Creator 'made them male and female,' 5and said, 'For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh'? 6So they are no longer two, but one. Therefore what God has joined together, let man not separate." (Matthew 19:4-6)
The math here is simple: 1 man + 1 woman = 1 marriage.
God said it, Moses wrote it, Jesus agreed with it.
As an acquaintance is fond of saying, "two or three witnesses".
As Barbie says, though, "Math is hard."
Is this a deep defense of historical Christian marriage? No, but I find that where there is much verbage, there can be much obfuscation. If the Gospel is simple (not simplistic), I find that it can work to be simple in explanations. (...as a little child, mayhaps?)