Deuteronomy 25:5-10, Levirate Law
A reader raises the topic of the Levirate arrangement in the OT where a brother would take his brother’s widow to wife and raise children to him (see Deuteronomy 25:5-10; the word "levirate" comes from the Latin levir meaning "husband’s brother"). He wonders about such structures and about polygamy and concubinage. I'm certain he’s right when he implies that polygamy and other institutions like it fall short of the one flesh union God gifted humans with and purposed for his glory and their enrichment. In that respect there's something "adulterous" about all those arrangements. As you know very well, they were regulated by God rather than approved.
Why God would tolerate these arrangements is another question. The reader and I are both committed to the view that God does what is right whether we understand it or not, but sometimes it's hard to follow God’s thinking. This is one of those areas where I find his "argument" hard to follow.
If we knew as much as he does (and I don't mean if we were omniscient) we'd understand the larger context of the tolerance. Sometimes it isn't a question of having specific knowledge on an issue—it’s a stress or a higher value on this or that that's missing in us. And sometimes the value is not in the arrangement itself or its immediate function, but in what is to be gained in the long term.
But beyond that—and this needs to be stated and developed with care—I’m persuaded that the patriarchal dominance that’s taken for granted in the OT is (in part) the outworking of the curse outlined in Genesis 3:16. We don’t hear of God regulating structures where women have numerous "husbands" or of legislation about women divorcing husbands because they find something in them that displeases the wives. As Genesis 3 tells it, both male and female united in sinning against God and redemptive chastisement falls on them. Sinful men exploited women—this was the outworking of God’s curse so it’s a combination of divine appointment and human wickedness. He means it for good and we mean it for evil, as it was in the cross of Christ and a host of human structures. To examine biblical laws and structures in (near) isolation, as independent realities, misses the full picture. I think the above needs to be borne in mind when we looks at things like polygamy, "slavery" (in some forms), concubinage and Levirate structures.
Certainly the Levirate arrangement had ramifications for the inheritance and the continuation of the name of the brother and that is what seems prominent in the texts dealing with the structure. But I think the land promise as it functioned within Israel has other and larger concerns—it has typological/theological ramifications and when we enter the gospel era, in the exaltation of the Christ, that piece of land is enlarged to the entire planet (see Romans 4:13). Land in the Bible is not just "turf". It's that, but it's also a token of "life with God". A major stress on the land inheritance throughout scripture is that God provides it to the powerless. It is always "gift" and cannot be seized or shrewdly gained in a sinister way. God saw to it that Abraham's "dead" body and Sarah's "dead" womb did not keep them from family and land and this Levirate arrangement may have something of all that in it. The "gospel" is being proclaimed in it as it is in other Israelite structures such as the redeeming of the firstborn, the Passover, and so forth. I'm sure that there is much more involved in God's regulating the Levirate arrangement than the immediate social/economic benefits. (It won't hurt to remark that all the social/economic benefits have a larger context within "the favour of God.")
Since God saw fit to tolerate and regulate polygamy and concubinage maybe we shouldn't be surprised that a Levirate arrangement was constructed (given the other considerations just hinted at). If it should be said—and it should be—that it is less than Genesis 2 and God's heart's desire, we should acknowledge it. Then, I suppose, we'd begin to speak of God gaining his ultimate ends in and through sinful people rather than the innocent ones he created in the Garden. Either obliterate sinners completely or gain your end through the realisable best until your ultimate holy aim is achieved. Maybe that's what faced God.
The above, I think, still stands, but it's clear that God didn't see the brother raising up a family to his dead brother as a casual thing. He slew Onan for getting the pleasure while treacherously taking advantage of his dead brother and his widow (Genesis 38:8-9). The same is true in the matter of concubines. There can be no suggestion that concubinage satisfied the heart of God, but a concubine was regarded as a wife (a wife with fewer "legal" rights). Reuben was rejected in favour of Judah because he slept with his father Jacob's concubine (Genesis 35:22 and 49:3-4). So polygamy, concubinage and the Levirate structure were not cases of people just "sleeping around". These were serious social structures that God made use of in gaining his greater ends. How he could do that is to be wondered at in many ways, one of them is that it is a marvel of grace and patience, and, in addition, as redemptive chastisement.