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
Muir, Marcus Dods and others have suggested that Muhammad was at first sincere, but later became deceptive. Koelle finds "the key to the first period of Muhammad's life in Khadija, his first wife," after whose death he became prey to his "evil passions." Samuel Marinus Zwemer, a Christian missionary, criticised the life of Muhammad by the standards of the Old and New Testaments, by the pagan morality of his Arab compatriots, and last, by the new law which he brought. Quoting Johnstone, Zwemer concludes by claiming that his harsh judgment rests on evidence which "comes all from the lips and the pens of his [i.e. Muhammad's] own devoted adherents."