For the gifts and the calling of God are irrevocable.
The text of rulings started in Exodus twenty can take us back to a time of cultural irrelevancy to the point that we may wonder about their current usefulness. Somehow though, these things about buying and selling children, slavery and polygamy are part of the great Horeb oracle, so to consider them irrelevant can be, and is in my opinion disrespectful.
Let’s look for example at the laws of polygamy. If he (a man) takes another wife to himself, he shall not diminish her (the first wife) food, her clothing, or her marital rights (conjugal intimacy). And if he does not do these three things for her, she shall go out for nothing, without payment of money (Exodus 21:10-11). Read from our modern western cultural viewpoint, these rulings sound barbaric; but while understanding them within their own merit and context, let’s give them a fair try.
Polygamy was an accepted Middle-East lifestyle in the days of Exodus when marriage was a business transaction. If he could afford it, a man could marry a woman for financial, political, or just plain lustful selfish reasons and once she served her 'purpose', get himself a new one to the neglect of the first one. Apparently God did not approve of this practice so He decreed that if a man re-marries, the food, the clothing and the conjugal rights of the first wife are not in any way to be diminished. If the husband doesn’t hold to that, she has automatic legal grounds to leave him and even remarry. In a certain way, that makes polygamy impossible unless you are as rich as Solomon.
We now are a far cry from these days of healthy ‘woman’s rights’. Today a man can take a woman, and if he has affairs on the side that cause him to neglect the first wife, she has to go through the cruel humiliations of being rejected in public divorce proceedings. This ruling teaches about the heart of the Father against such cruelty as rejecting a wife.
A common teaching today is replacement theology: the ideology that because of sin God rejected His first wife Israel in favor of Christianity. For many, this explains our on-going exile, the inquisitions and the Holocaust. People easily understand replacement theology scenario because of the way they live and generally understand God through the lenses of their own perverted divorce-accepting viewpoint. First, God hates divorce (Exodus 20:14; Matthew 10:2-9), and as far as Israel is concerned, Paul explains that, “the gifts and the calling of Hashem are irrevocable (Romans 11:29)”. First, if God practices the irrevocable putting away of wives because of sin, Christians are also in danger. Second, even if He did, our relationship with Him was not to be diminished.
My point here is that this commandment reveals the true nature and character of the Father. He may chastise us for awhile to help us know and trust Him more, but never in an attempt to drive us away from Him, and He doesn’t go from ‘bride’ to ‘bride’ as mankind seems to enjoy doing today. We can now see not that this seemingly archaic rule teaches us much about our current value system and even our theology.