A husband must consult his wife because at the time of marriages the Holy Prophet sas would recite the verse:
O ye who believe! Fear Allah, and say the straightforward word.(Surah al-Ahz- ab, 33:71)
Also, the husband should give serious consideration to sacrificing for the sake of the sentiments of his first wife. The Promised Messiah as wrote:
A husband should have such regard and respect for the feelings of his first wife, that if he feels the need of a second wife, but is afraid that it would hurt his first wife and break her heart, in such a case, if he can exercise restraint without falling into sin and without sacrificing his lawful needs, it would be preferable for him to forego the advantages of a second marriage for the sake of comforting his first wife.(Essence of Islam, vol. 3, p. 321)
However, polygamy is the assumed right of the husband. The Promised Messiah as wrote:
Women have the right to lay down the condition that the husband will, in no circumstance whatsoever, marry another woman. If this condition is laid down before marriage, the husband will be guilty of breach of contract if he goes on to marry another. But if a woman does not prescribe any such condition, and is content with the law as it is, an outsider has no right to interfere. In such a case, the proverb seems relevant: “If the husband and wife are happy, the qadi has nothing to do.”(Essence of Islam, vol. 3, p. 318)
Although the husband can forgo this right, initially it is his. For example, if someone has no intention of paying his dowry, he will still be required to pay it. The fact that he did not know he actually has to pay it does not make any difference. His wife does not need to request him to give her dowry. In a Muslim marriage, actually receiving the dowry is the basic and assumed right of the wife, whether the husband is aware of it or not. In a Muslim marriage, polygamy, like other rights and responsibilities, is the assumed right of the husband, whether the wife is aware of it or not.
This is the reason why a Muslim man does not need to give a reason for wanting to marry a second wife, Islam has given him this right. The Holy Prophet
Hudur ra said that when men are marrying a second time, they try
to come up with reasons and excuses, but Islam has given them this right, they do not need an excuse to marry a second time (Khutbat-e- Mahmud, vol. 3, Khutbat-e-Nikah, p. 393–396).
So long as the basic condition of justice is fulfilled, this decision is left to the consent of the bride and groom. Each man must decide with righteousness if polygamy is best for him according to his personal needs. Some of these needs have been explained, the rest have not. Hadrat Khalifatul-Masih IV rta said:
The Promised Messiah as did not individually explain the details of these needs because the circumstances of different men are different, their responsibilities are different, their needs are different, each man is not of one type. As in science, there are valencies. Some chemical elements can bond with one another, some with two, some with three, some with four, and here it ends. Similarly, in men, Allah Almighty has created different temperaments of people, and their capacities have been made lesser and greater. Since this subject would have become very detailed, and since many such things would have needed to be explained which the Promised Messiah as wanted to abstain from, so, after giving an indication, he has left it. Thus this conclusion does not in any way result that he said to fulfill one need and that is it. It means that there is a possibility of fulfilling one need, beyond that, you know. But remember that justice is the condition.(Dars-ul-Quran, 27th, January 1996, Surah an-Nisa’, 4:4)
It is essential to understand this point because not understanding it causes misunderstandings on so many other points. The reason a man does not need his first wife’s permission is that, in Islam, the right to polygamy is assumed in a marriage. Hadrat Khalifatul-Masih IV rta said:
There is no mention of this anywhere, either in the Holy Quran or the tradition, that it is binding upon man to take permission of his wife before deciding to marry again.(Question Answer Session, Feb 22, 1985)
However, just because he does not need his wife’s permission does not mean that he is free to do as he pleases. The Holy Quran has taught that a man must be able to support all of his wives to marry more than once (Khutbat-e-Mahmud, vol. 3, Khutbat-e-Nikah, p. 478).
The Holy Quran and the Holy Prophet
You may marry two or three or four of them provided you can deal equitably with all of them. But if you feel that you may not deal justly between them then marry only one, even if you should feel the need of more than one.(Ruhani Khaza’in, vol. 10, p. 337)
Explaining this, Hudur aba said:
The sentence, “even if you should feel the need of more than one” is very meaningful. Saying this, the Arbiter and Judge of this age has decreed that(Friday Sermon, May 15, 2009, p. 5)
yourneed, which you use as an excuse to want to marry, does not have real importance. Rather, the peace of society and justice are the real issue. These days, from one place or another, complaints keep coming that although aman has children, he makes various excuses and wishes to marry. Firstly, it is commanded that if you cannot do justice, then do not marry. In justice, fulfilling every type of responsibility is included. If you do not have enough income to run a household, then to take on the burden of another marriage is stealing the rights of the first wife and children. The Promised Messiah as said in one place that if a person has to marry again out of necessity, then he should care for his first wife better than before. However, these days what we practically see in society is that husbands slowly ignore fulfilling the rights of the first wife and children completely. They act against the command of Allah Almighty.
No matter how genuinely the husband needs to marry a second time, if he cannot do justice, he cannot marry again. Hadrat Musleh Mau‘ud ra said:
If a man does not do justice between his wives, he should be excommunicated from the Jama‘at because he disgraces Islam.(Fatawa Hadrat Musleh Mau‘ud, vol. 2, p. 55)
The only area where he is not required to be perfectly just is in equally dividing his feelings of love since this is not in a person’s control (Holy Quran English w/ 5 Vol. Commentary, p. 568). These restrictions are not easy to meet, and that is why polygamy can only be practiced by a minority of Muslims.