So my question is, regardless of the reason and rationale for the desire for polygyny (Biblical, needing more love/support, etc), when a man desires more than one wife is he ever likely to change?
Is this something he will always want even if he doesn’t act on it?
I believe if a man desires more than one wife, he will likely always want more, but may never act on those desires. I'll get more into that in a bit.
I guess I’m curious that if a man expresses interest in this, but says he will abandon interest for the sake of an existing wife, is it reasonable for her to expect that he will not be interested going forward?
No, it's not reasonable. All men are somewhat interested in having more than one woman. It's in a man's nature.
In We Want For Our Sisters What We Want For Ourselves the depiction tends to be more that this is an innate desire and immutable characteristic harnessed for the glory of God. But that book focuses on African American culture. I’m wondering if it’s more broadly true across cultures?
I think in my experience and speaking to men, that yes it's a broadly applicable characteristic of mankind. Women even if they say they're not hypergamous are innately drawn that direction. Men, even if they say they're strictly monogamous are polygynous by nature. A nice figure sauntering past in a tiered skirt and tank top (or whatever is his particular flavor) is always going to draw the eye. He will always be drawn by animalistic desire to conquer another. He may stifle those drives, or he may be so messed up hormonally that he's effectively neutered, or he may have such self mastery as to constrain his thoughts and actions to remain monogamous. But I contend that there will always be an internal pressure.
There is a duality at play, there's the more childish, passion, lust, animalistic sexual drive of having more that I think all healthy men will always have. But there's also the mature agape love that a man has in wanting to see a woman protected and cared for. If he already has one wife and children, he will prioritize the safety and protection of the first over a possible second if he's wise. And most men just simply aren't capable of juggling the needs and concerns of multiple women. There's a TREMENDOUS amount of complexity to navigate, and while I'm confident in my ability to do so, I still find myself hesitant to push my own limits in that regard. I think I know how much work it's going to take. But I know my depth of knowledge and understanding is the same as when my first child was as yet unborn. I knew how much work it was going to take, but my knowledge was limited and after walking through it learned how little I really knew. It's this understanding that gives me pause and forces me to be very careful in consideration of prospective women. (Dunning-Kruger)
I've personally passed on numerous women looking to by my second. I've had fathers ask to betroth their daughters to me. I have options, but like others have said, there's a price to be paid. That's why I still have one wife. I would definitely benefit were I to take another wife, my income would likely double just having help writing books and managing clients and helping with accounting.
So while I can see the benefits, and can understand the positives, and I have opportunities to make that change a reality in my life. I still haven't pulled the trigger so to speak. Because it's a complicated matter and it's serious stuff!
So yes, I think men will always desire polygyny once they realize that it's acceptable before God. But only the fools/naïve and truly exceptional men will ever pursue it. And if a man's not led his first wife well enough to have her submission and support in the matter, he has rock solid proof that he is not in that "exceptional" category and should not pursue adding another. A wise man will ensure he will not destroy the house when building an addition onto it.
His first wife should trust him enough that even if she has fear and trepidation about the difficulties, that she will say "Not my will but yours, I will follow you wherever you bring me."
