Khadeejah, (رضي الله عنها), was a business woman possessing much nobility and wealth. When news reached her of Muhammad’s trustworthiness, she called for him and presented him with the opportunity to take some of her money to the area of Shaam to do business with. And she told him she would send him with more money than other traders (under her service), along with her servant (boy), Maysarah.
So Allaah’s Messenger (صلى الله علیه وسلم) accepted the proposition and set out with her money accompanied by her servant. When he returned to Makkah, she saw the honesty with which her money was handled and the blessing it received (i.e. profit). She did not see this kind of results in the past (from other traders). Also, Maysarah informed her of what he saw in Muhammad (صلى الله علیه وسلم) from his pleasant nature, nice characteristics and honest way of dealing. So when she saw and heard this, along with what he was informed of by the monk (Bahira), that Muhammad would be a Prophet, she found what she had been looking for. So after this, she talked to her friend, Nafeesah bint Maniyyah, who then went to Allaah’s Messenger (صلى الله علیه وسلم) to talk him into marrying Khadeejah. He was pleased with it and accepted. 
The Marriage of Khadeejah
The Messenger of Allaah (صلى الله علیه وسلم) married her and gave her ten camels as her dowry. It was said that her father married her while he was drunk. Then when he became sober, he said:
“Who said that I married her off?” So he went to Allaah’s Messenger (صلى الله علیه وسلم), looked at him and said: “If I married her to you, then that is my choice. And if I didn’t do it, then I marry her to you.”
At the time of their marriage, Khadeejah was forty years old and Allaah’s Messenger (صلى الله علیه وسلم) was twenty-five. She was the first woman Allaah’s Messenger married, and he did not marry any other woman while married to her, until she died. She gave birth to all of his children except for Ibraaheem, who was born from Maariyah, the Coptic.
The first child she bore for him (صلى الله علیه وسلم) was Al-Qaasim, for whom he took his kunyah after. Then she bore Zaynab, Ruqayyah, Umm Kulthoom, Faatimah and ‘Abdullaah, who was nicknamed Tayyib and Taahir. All of his sons died in their childhood. As for his daughters, all of them reached the advent of Islaam, accepted it and made the Hijrah (to Madeenah). However, all of them died during the Prophet’s lifetime, except for Faatimah, (رضي الله عنها), for she died six months after his death.
Her Support for the Prophet in the First Stages of the Revelation
Khadeejah would back up and support the Prophet (صلى الله علیه وسلم) during all of his crises and times of distress. She had magnificent and wonderful examples showing her support for the Prophet, in which she would fortify his determination and firmness during difficult times.
An example of this was when he (صلى الله علیه وسلم) was frightened by the revelation that came down to him in the Cave of Hiraa. So he returned to Khadeejah saying:
“Cover me, cover me.” So they covered him until his fear went away. Then he turned to Khadeejah and informed of what had happened, saying: “I feared for my self (i.e. my life).” She said: “No, by Allaah. Allaah will never disgrace you. You keep ties with the kin, you bear the burdens of the weak, you help the poor and the needy, you are kind to the guests and you suffer hardships in the path of truth.”
This is part of a hadeeth reported by Al-Bukhaaree from the narration of ‘Aa’ishah (رضي الله عنها).
Her Life after Accepting Islaam and Her Virtue
Khadeejah, (رضي الله عنها), was one of the gracious blessings Allaah bestowed on His Messenger (صلى الله علیه وسلم). She remained with him for a quarter of a century, showing him affection at times of unease and supporting him during his most painful moments. She assisted him in conveying his Message and she would contribute to the financial obligations of Jihaad. And she would aid him with her self and her wealth.
Allaah’s Messenger (صلى الله علیه وسلم) said about her in the last part of this hadeeth, as reported by ‘Aa’ishah (رضي الله عنها):
“Allaah’s Messenger would not leave from my house until he has mentioned Khadeejah and praised her. So one day, he praised her in my presence and I felt jealousy, so I said: ‘What was she but an old woman. Allaah has replaced her for you with someone better (meaning herself).’ So he became angry to the point that the front of his hair convulsed due to his anger. He then said: ‘No by Allaah, He has not replaced for me someone better than her. She believed in me when the people rejected me. And she held me to be honest when the people said I was a liar. And she supported me with her wealth when the people withheld from me. Allaah blessed me with children through her when He prevented me from having children from other women.’ So I said to myself: ‘I will never mention her in a bad way again.’” [Reported by al-Bukhaaree, Muslim and Ahmad]
It is recorded in the Saheeh, from Abu Hurairah (radi-Allaahu ‘anhu) that he said:
“Jibreel came to the Prophet and said: “O Allaah’s Messenger, this is Khadeejah coming with a vessel in which there is meat soup or (some) food or drink. So when she comes to you, then convey the Salaam to her on behalf of her Lord, and give her the tidings of a palace in Paradise made from brocade and with pearls in the interior, where there will be no noise or fatigue.”
And the Prophet (صلى الله علیه وسلم) said:
“The best of its (Paradise’s) women is Khadeejah.” [Reported by al-Bukhaaree from the narration of ‘Alee (رضي الله عنه)]
And he said:
“Khadeejah was indeed given virtue over the women of my Ummah, just as Maryam was given virtue over the women of all the worlds.” [A hasan hadeeth reported by al-Bazaar and at-Tabaraanee from ‘Ammaar bin Yaasir (رضي الله عنه)]
The Prophet (صلى الله علیه وسلم) said:
“The best of the women of Paradise are: Khadeejah, Faatimah, Maryam and Aasiyah.” [Reported by an-Nasaa’ee with an authentic chain. Al-Haakim reported it from Ibn ‘Abbaas (radi-Allaahu 'anhumaa)]
It is said she died ten years after the advent of Islaam, during the month of Ramadaan. The year she died was known as the Year of Grief, because the Prophet (صلى الله علیه وسلم) lost his best supporter. She was the best of those who aided him and the strongest of those who encouraged him.
The Prophet (صلى الله علیه وسلم) would not grow tired of mentioning her, due to the great status she held in his heart, not to mention the hearts of the believing men and women. This is how Khadeejah must be in our hearts as well. So whoever Allaah and His Messenger love, we must love him/her also. [Ar-Raheeq al-Makhtoom (pg. 51-58) and al-Bidaayah wan-Nihaayah (2/274)]
 Translator’s Note: Imaam Ibn al-‘Uthaymeen said in Sharh Lum’atul-‘Itiqaad:
“Khadeejah Bint Khuwailid - She was the mother of all his (صلى الله علیه وسلم) children, except Ibraaheem. The Messenger of Allaah (صلى الله علیه وسلم) married her after she had been married twice before. Her first husband was 'Ateeq bin 'Aabid and the second was Abu Haala At-Tameemee. He did not take a second wife while married to her, until she died in the 10th year of Muhammad’s prophethood, before the Mi'raaj.”