Muhammad's wives
Muhammad was monogamous for 25 years. After his first wife Khadija bint Khuwaylid died, he proceeded to marry the wives listed below, and most of them were widows. Muhammad's life is traditionally delineated as two epochs: pre-hijra (emigration) in Mecca, a city in western Arabia, from the year 570 to 622, and post-hijra in Medina, from 622 until his death in 632. All but two of his marriages were contracted after the Hijra (migration to Medina). Of Muhammad's thirteen wives, at least two, Rayhana bint Zayd and Maria al-Qibtiyya, were referred to simply as concubines; however, there is debate among Muslims as to whether these two officially became his wives. Of his thirteen wives, only two bore him children, a fact which has been described as "curious" by Cornell University Professor of Near Eastern Studies David S. Powers.
Criticism of Muhammad
The marriage was used by Munafiqs of Medina to discredit Muhammad on two fronts, one of double standards as she was his fifth wife, while everyone else was restricted to four, and marrying his adopted son's wife. This was exactly what Muhammad feared and was initially hesitant in marrying her. The Qur'an, however, confirmed that this marriage was valid. Thus Muhammad, confident of his faith in the Qur'an, proceeded to reject the existing Arabic norms. When Zaynab's waiting period from her divorce was complete, Muhammad married her. In reference to this incident, Sura Al-Ahzab says: