The Messenger of Allah (S) married Lady Khadija at the age of twenty-five, while Khadija herself was forty years old. Yet some historians allege that she was twenty-five, and still others claim that she was twenty-eight years old.
It is also said that she had two previous marriages before marrying the Prophet (S) some historians dispute this and indicate that she was a virgin when the Last Prophet (S) married her. This last claim is not common.
The Prophet's marriage to Khadija was not a usual one. It was a unique marriage because it was not initiated as a result of a love relationship, nor, was there a material, or, political motive behind it, which was commonplace among the elite classes. In fact, there was no correlation between the Prophet's economical position and that of the Lady Khadija's. On one hand, the Messenger was sponsored by his poor uncle, Abu Talib, and on the other hand, Khadija was the wealthiest lady in Mecca. Thus, there was an evident gap between them in this peculiarity.
Khadija heard that the Prophet had a bright and sacred future ahead of him; perhaps she heard this from her servant Maisarah, who informed her of what had happened to the Messenger during a commercial trip to Syria in which he had worked for her. Or perhaps he conveyed to her what the monk in Busra said about the future of the Prophet-upon learning this, Lady Khadija suggested that prophet Muhammad (S) marry her, and urged him to ask for her hand from her Father, Khuwaylid (according to some historians it was her uncle).
The Prophet, who preferred to marry a poor woman from his own economical class, apologized to Khadija and refused her request. But, she being a wise, reasonable, and honorable woman informed him that she was ready to grant him herself, and that property was not a difficult thing to put at his disposal. So, she once again urged him to send his uncles to ask for her hand from her Father, Khuwaylid.
The Prophet's uncles and aunts were astonished at this news; a very wealthy lady who sponsors hundreds of people, and tens of men work for her in her property and trade for her throughout the summer and winter seasons, between Yemen, Mecca and Syria; a great Lady whom the noblemen had asked to marry, but she had refused them all, giving herself to a poor Quraishan young man, sponsored by his poor uncle, Abu Talib!! Could she have been honest in doing so?! Could this news be true? Safiya bint Abdul Muttalib (the Prophet's aunt) rushed to Khadija's house to validate the news. She was warmly welcomed by Khadija who informed her of her earnest desire to do so.