Khadija was the daughter of Khuwaylid ibn Asad, a prominent member of the Quraysh. Her grandfather Qusayy was related to ancestors of Prophet Muhammad. Khadija, who was married twice before marrying the Prophet, was a noble, beautiful and rich woman. She received several marriage proposals from leading figures of the Quraysh after the death of her second husband, but she refused all of them. Khadija made her living through trade, with people whom she considered reliable. Upon advice she had received, Khadija contracted a partnership agreement with Prophet Muhammad, known in society as a dependable young man of high morality. She asked him to go to Syria for trade with her slave Maysara. This journey to Syria was very successful in terms of trade. Khadija was very pleased with this success and witnessed his reliability and trustworthiness firsthand. Listening to Maysara’s awe-inspiring words of praise of the Prophet’s virtues and behavior, Khadija trusted Muhammad even more and her feelings of admiration for him grew stronger as the days went by. According to narration, Khadija proposed marriage to Prophet Muhammad some time after this, either personally or via a woman named Nafisa bint Umayya (Munya). Coming as a surprise to him, the Prophet accepted this proposal after some consideration. Abu Talib and the Prophet’s other uncles asked for Khadija's hand in marriage from her uncle ‘Amr ibn Asad, as her father was no longer alive at the time. Upon receiving an affirmative reply, the marriage was conducted. Prophet Muhammad moved from Abu Talib's house to Khadija's house and thus a happy household was formed. It is recorded that Prophet Muhammad was twenty-five years old and Khadija was forty years old at the time. There are accounts, however, which assert that Khadija was younger than forty at the time of the marriage.
The couple had seven children; Qasim, Zaynab, Ruqayyah, Umm Kulthum, Fatima, ‘Abd Allah (Tayyib), and Tahir. ‘Abd Allah and Tahir died before the Prophethood of Muhammad. Some sources state that Tayyib and Tahir were two different children, while others assert that these were both nicknames for ‘Abd Allah. Except for his youngest daughter Fatima, the Prophet's children all died before him. Fatima lived six months after the Prophet’s demise. Prophet Muhammad assumed the kunya, or name honorably given to a child’s father, Abu al-Qasim because of his eldest son Qasim. Two others joined the household of the Prophet during his marriage with Khadija. One of them was Zayd ibn Harith, a slave given to him by Khadija, whom he set free and later adopted. The second was ‘Ali ibn Abu Talib, the son of his uncle Abu Talib, who is narrated to have been five years old at the time and who he took in, in support of his uncle; Abu Talib faced great financial difficulty due to a drought which occurred in Makka. The Prophet later wed his daughter Fatima to ‘Ali and his lineage continued through his much-loved grandchildren Hasan and Husayn.
Khadija ceaselessly supported Prophet Muhammad, both materially and spiritually, throughout their marriage of twenty-five years. Being the first person to believe in the Prophet, Khadija remained by his side during the most difficult of times. She is the first wife of the Prophet and the mother to all his children with the exception of Ibrahim. The Prophet never forgot her goodness and her devotion. As is known, Prophet Muhammad did not marry any other woman while Khadija was alive, and contracted all his other marriages after her passing, based upon several important reasons. The Prophet always remembered Khadija with kindness and once said of her: "God has not given me better than her. She believed in me at a time when everyone else denied my Prophethood. She affirmed me when everyone else spurned me. She put all her wealth at my service when other people withheld theirs from me. And what's more, God gave me children through Khadija."