“And if you fear that you will not deal justly with the orphans, then marry other women those that please you, two or three or four. But if you fear that you will not be just, then marry only one or those your right hand possesses. That is more suitable that you may not incline to injustice.“ (Qur’an 4:3)
Some people may ask, why can men marry up to four women and Muslim women cannot marry up to four men? In reality, the only answer that a Muslim needs to give is: “Because Allah, the Creator of this universe, full of Wisdom has not decreed this.”
The following reasons that I give are actually for those with sickness in their hearts. Those who struggle with understanding that Allah (swt) is full of wisdom and understands the intricacies of his creation better than anyone.
The problem with giving reasons or plausible scenarios is that someone can come along with better reasons that will undermine the reasons that you give. So here are some plausible reasons.
If a man has four wives and they are all pregnant we know who the father is. We also know who the mother of all four of the children is. They are the ones who carried them in the womb for 9 months and then delivered the children.
If the scenario is reversed a woman has four husbands we know who the mother is but who exactly is the father? There is nothing wrong with the child wanting to know who his/her father is. Who is the one who gave life to me? Whose characteristics do I take after?
Now someone can reply that one can take a DNA test. In that scenario, one must keep in mind the cost of the DNA tests. The availability of DNA tests. This in and of itself is simply not practical for implementation everywhere on the Earth.
The other issue with the four men sharing one woman is that each of them may be thinking he is the father of the child. This may also lead to a scenario where each of them thinks they are healthy where it is plausible that one of them may actually be infertile.
This could be quickly identifiable with a man who has four wives. If none of the wives are ever getting pregnant we know something is going on medically speaking. If a woman has four husbands and she gets pregnant we are not able to tell which of those men may have infertility as a medical condition.
Not to imagine what the inheritance laws begin to look like.
When you factor in natural occurrences like death, divorce, re-marriage, and that in a plausible scenario at any given time anyone woman could have four husbands and any one man could have four wives, it looks to me that the laws of inheritance will become an absolute mess.