Juwayriyya bint Harith, may Allah be pleased with her, married the Prophet Muhammad (peace and blessings of Allah be upon him) in 5 AH, when the Prophet was fifty-eight years old and she was twenty, not long after his marriage to Zaynab bint Jahsh, and as a result of the Muslims ' successful campaign against the Banu Mustaliq who were swiftly defeated after the Prophet's surprise attack. Among the captives taken in this campaign was the beautiful Juwayriyya, the daughter of al-Harith, who was the chief of the Banu Mustaliq. She was afraid that once the Muslims realized who she was, they would demand an exorbitant ransom for her safe release. After the Muslims had returned to Medina with their booty and prisoners, she demanded to see the Prophet Muhammad (peace and blessings of Allah be upon him) hoping that he would help to prevent what she feared. Seeing how beautiful she was, A'isha was not keen on her seeing the Prophet.
But she persisted, and eventually she was permitted to see the Prophet (peace and blessings of Allah be upon him) and was taken to him while he was with A'isha. After she had finished speaking, the Prophet thought for a moment, and then said, "Shall I tell you what would be better than this?"
He then asked her to marry him, and she immediately accepted. Although Juwayriyya was young and beautiful and of noble lineage, the Prophet (peace and blessings of Allah be upon him) was thinking of how to save her and all her tribe from an ignoble fate. By marrying Juwayriyya, the Banu Mustaliq would be able to enter Islam with honor, and with the humiliation of their recent defeat removed, so that it would no longer be felt necessary by them to embark on a war of vengeance that would have continued until one of the two parties had been annihilated. As soon as the marriage was announced, all the booty that had been taken from the Banu Mustaliq was returned, and all the captives were set free, for they were now the in laws of the Prophet Muhammad (peace and blessings of Allah be upon him). Thus A'isha once said of Juwayriyya, "I know of no woman who was more of a blessing to her people than Juwayriyya bint al-Harith." After they were married, the Prophet (peace and blessings of Allah be upon him) changed her name was Barra to Juwayriyya.
It has been related by Juwayriyya that early one morning the Messenger (peace and blessings of Allah be upon him) left her room while she was doing the dawn prayer. He returned later that morning and she was still sitting in the same place. "have you been sitting in the same place since I left you?" he asked. "Yes," she replied. Whereupon the Prophet said, "I recited four phrases three times after I left you, and if these were to be weighed against what you have been reciting since dawn, they would still outweigh them. They are: 'Glory be to Allah and Praise be to Him as much as the number of his creations, and His pleasure, and the weight of His Throne, and the ink of His words.'" Which reminds us of the following ayat of the Qur'an:
Say: 'If the sea were the ink for the words of My Lord, truly the sea would be used up before the words of my Lord were completed, and even if We used the same again to assist. (Qur'an 18:109)
Juwayriyya was married to the Prophet (peace and blessings of Allah be upon him) for six years, and lived for another thirty-nine years after his death, dying in 50 AH at the age of sixty-five, may Allah be pleased with her.