Musnad Abu Ya'la al-Mawsili 226:2

Abu Sa’id al-Jashmi narrated to us, he said: ‘Alila bint al-Kumayt narrated to us, she said: I heard my mother, Amina, say: Amat Allah bint Ruzayna narrated to me, from her mother, Ruzayna, the freedwoman of the Messenger of Allah (may Allah bless him and grant him peace): That he took Safiyya captive on the day of Qurayza and al-Nadir when Allah granted him victory. He came with her, leading her as a captive. When she saw the women, she said: "I bear witness that there is no god but Allah and that you are the Messenger of Allah." So he released her, and her arm was in his hand. Then he emancipated her, proposed to her, married her, and gave her a dowry.