On the day of the Confederates, Umar bin Abu Salama and I had been placed among the women. I looked out and saw Zubayr riding his horse, going back and forth toward the tribe of Banu Qurayza two or three times. When he returned, I said, "Father, I saw you going back and forth."He asked, "Did you really see me, my son?"I replied, "Yes."He said, "The Messenger of Allah ﷺ had asked, 'Who will go to Banu Qurayza and bring me news of them?' So I set out. When I returned, the Messenger of Allah ﷺ joined both of his parents in pledging them for me, saying, 'May my father and mother be your ransom.'"
كنت يوم الأحزاب جعلت أنا وعمر بن أبي سلمة في النساء، فنظرت فإذا أنا بالزبير على فرسه يختلف إلى بني قريظة مرتين أو ثلاثا، فلما رجعت قلت: يا أبت، رأيتك تختلف، قال: أوهل رأيتني يا بني؟ قلت: نعم. قال: كان رسول الله ﷺ قال: من يأت بني قريظة فيأتيني بخبرهم، فانطلقت، فلما رجعت جمع لي رسول الله ﷺ أبويه، فقال: فداك أبي وأمي.
Bukhari narrated it in Fadail al-Sahabah (3720), and Muslim in Fadail al-Sahabah (2416), both through Hisham bin Urwa, from his father, from Abdullah bin Zubayr, who said, and then related it. This is the wording of Bukhari. In the wording of Muslim it reads, "with the women in the fortress of Hassan," and in another wording of his, "in the fortress where the women were, meaning the wives of the Prophet ﷺ."