It is narrated from Sayyidah Aishah (may Allah be pleased with her); she said: On the day of (the Battle of) the Trench, I saw a man in the likeness of Dihyah bin Khalifah al-Kalbi, riding a mount and speaking privately with the Messenger of Allah (peace and blessings be upon him). On his head was a turban, one end of which he had let hang down over his face or shoulders. I asked the Messenger of Allah (peace and blessings be upon him) about him, and he (peace and blessings be upon him) said: "That was Jibril (peace be upon him); he has commanded me to march out against Banu Qurayzah." This hadith has a sahih (authentic) chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.