The Fifth, the Captives and Rayḥānah

Again, the men were killed and the property was divided. Ibn Isḥāq narrates how the one fifth was disposed of. Because this was a war, four fifths of the ghanīmah was divided amongst the fighters, and the remaining one fifth was given to the Messenger of Allah (peace be upon him), and this is how he used it.

Ibn Isḥāq said: "The Messenger of Allah dispatched Saʿīd ibn Zayd^**** with the captives taken from Banū Qurayẓah to Najd, where he sold them in exchange for horses and weapons. The Messenger of Allah had chosen for himself one of their women, Rayḥānah. He stayed intimate with her until he died, she still being at that time in his household. The Messenger of Allah had suggested that she accept Islam, but she had refused. Eventually she did accept Islam, and this brought great pleasure to him. He suggested releasing and marrying her, but she chose to continue in slavery, considering that easier for her. She remained with him until the Messenger of Allah died."

So, slavery in Islam: Islam has changed many of the rules regarding this institution, to the extent that here you have a person who chooses to remain as a slave rather than be freed.