Islam is criticized for allowing polygamy, which the popular culture of the West considers polygamy to be rather backward and poor. For many Christians, it is a license for confusion and feminists consider it a violation of women’s rights and humiliation. An essential point to understand is that for Muslims, the standard of morality is not determined by current Western thinking, but by divine revelation. There are a few simple facts to keep in mind before speaking about polygamy in Islam.
Islam did not introduce polygamy
Islam did not introduce polygamy. Polygamy was a recognized institution among the ancient Eastern peoples. Polygamy has existed among Hindus since the earliest times. There was no limit to the number of wives a man could have among the ancient Babylonians, Assyrians, and Persians. Although the Greeks and Romans were not polygamous societies, concubines were the rule there.  Islam established rules for polygamy by restricting the number of wives and emphasizing responsibility. In fact, according to David Murray, an anthropologist, historically polygamy was more common than monogamy. 
Polygamy from the Prophets of God
The great Hebrew patriarchs recognized by Judaism, Christianity, and Islam alike – Abraham, Moses, Jacob, and Solomon, to name a few – were polygamous. According to the Bible:
Abraham three women (Genesis 16: 1, 16: 3, 25: 1)
Moses two women (Exodus 2:21, 18: 1-6; numbers 12: 1)
Jacob four women (Genesis 29:23, 29:28, 30: 4, 30: 9)
David at least 18 women (1 Samuel 18:27, 25: 39-44; 2 Samuel 3: 3, 3: 4-5, 5:13, 12: 7-8, 12:24 , 16: 21-23)
Salomon 700 women (1 Kings 11: 3). 
The example of Jesus who endorsed polygamy is irrelevant because he did not marry during his mission on earth.
Marriage in Islam
Marriage in Islam is a legal agreement, not a sacrament as in the Christian sense, and is secured by a contract. An Islamic marriage establishes rights and mutual responsibility for every spouse. Children who would otherwise have been born out of wedlock are legally recognized and receive a share of the inheritance from their parents.
The main purpose of marriage in Islam is to regulate sexuality within marriage and to provide an atmosphere of steadfastness and expansion of the family. This is in sharp contrast to the spreading marriage trends in the West. In the past few decades, there have been more alternatives to marriage than ever before. Living together without marriage certificates has become widespread among young people, as have never married adults and divorced women. More and more American women have illegitimate children, ignoring the traditional sequence of getting married and then having children.
Polygamy in the Quran
The Muslim Scripture, the Quran, is the only script known in the world that restricts polygamy and sets strict rules for its practice:
“… get married, what suits you well in women, two, three or four. But if you are afraid that you won’t be able to treat her right away, then (marry) one. ” (Quran 4: 3)
The Quran restricted the number of wives to four. In the early days of Islam, people who wanted to adopt Islam and had more than four wives were required to divorce the excess. Islam reformed the institution of polygamy by making equal treatment of all women a requirement. The Muslim is not allowed to differentiate between his women in terms of their accommodation, maintenance and time division, as well as other obligations of the husband. Islam does not allow a man to marry another woman unless he is treated fairly. The Prophet Muhammad forbade any of his wives or children to be preferred.
Marriage and polygamy in Islam are also matters that require mutual consent. Nobody can force a woman to marry a married man. Islam only allows multiple marriages; he does not force it and it is not a duty. A woman can even specify in her marriage contract that her husband cannot marry a second wife. The point that is often misunderstood in the West is that women in other cultures – particularly African and Islamic – do not necessarily see polygamy as a sign of degrading women. Accordingly, equating polygamy with degrading women is an ethnocentric judgment by other societies.
Although polygamy’s permission is very clear, its actual implementation is fairly rare in Muslim societies. Some researchers estimate that no more than 2% of married male Muslims live polygamous.  Most Muslim men feel that they cannot afford to spend more than one family. Even those who could afford to support additional families are often reluctant because of the psychological stress that another woman places on them. It can be said with certainty that the number of polygamous marriages in the Muslim world is far less than the number of extramarital affairs in the West  In other words,
 “The only important peoples of antiquity who showed little or no traces of it [(polygamy)] were the Greeks and the Romans. However, the concubinate, which can be seen as a higher form of polygamy, or at least as monogamy, was recognized as a custom for many centuries and was even legal in these two societies. ” The Catholic Encyclopedia: (http://www.newadvent.org/cathen/09693a.htm)
 Cheryl Wetzstein, “Traditionalists Fear Same-Sex Unions Legitimize Polygamy,” The Washington Times Dec. 13. 2000.
 A detailed list of biblical figures who have practiced polygamy can be found at: (http://www.biblicalpolygamy.com/).
 Dr. Jumah al-Kholy, ‚Ta’addud al-Zawjaat wa Hikmatuhu fil Islam,‘ (Mehraub in Islam & their wisdom), Journal of the Islamic University of Medina, vol. 46, 222-231.
 The last definitive survey on sexual behavior showed that 20% of women and up to 35% of men were unfaithful to their spouses at one time or another. (Sex in Marriage, Little, Brown and Co., 1994, page 105). Another survey shows that adultery is as common among Christians as it is among non-Christians. Christianity Today magazine polled its readers and found that 23% admitted to having had extramarital sex. The Lutheran Church: Missouri Synod (http://old.dcs.lcms.org/family/Content%5Cdoc_articles%5C409.doc)