Abu Abd al-Rahman al-Fihri (may Allah be pleased with him) said: I was with the Messenger of Allah (peace and blessings be upon him) in the Battle of Hunayn. We travelled on a day of intense heat and camped in the shade of the trees. When the sun had passed its zenith, I put on my armour, mounted my horse and set off towards the Messenger of Allah (peace and blessings be upon him), who was in his tent. I said: As-salamu 'alayka ya Rasulallah wa rahmatullahi wa barakatuh (Peace be upon you, O Messenger of Allah, and the mercy of Allah and His blessings); has the time to set off come? He (peace and blessings be upon him) said: "Yes." Then he said: "O Bilal!" He rose up from beneath a tree in such a way that his shadow was like the shadow of a bird, and said: Here I am at your service; may I be your ransom. He (peace and blessings be upon him) said: "O Bilal, saddle my horse for me." So he brought out a saddle whose two side-boards were made of palm fibre, with no adornment or pride in them. When it was saddled, he (peace and blessings be upon him) mounted and we mounted too. We spent our evening and our night drawn up in ranks facing them. Then the two armies saw each other, and the Muslims turned their backs and fled, as Allah has said. The Messenger of Allah (peace and blessings be upon him) said: "I am the servant of Allah and His Messenger." Then he (peace and blessings be upon him) pressed forward on his horse and took a handful of dust. The one who was closer to him (peace and blessings be upon him) than I was told me that he (peace and blessings be upon him) threw it into their faces and said: "May the faces be disfigured," and so Allah defeated them. Ya'la bin Ata said: Their sons related to me from their fathers that they said: There was not one of us left whose eyes and mouth were not filled with dust, and we heard a clanging from the sky and the earth like iron being scraped over a basin. (This is the wording of Affan's narration.)
Hadith Referenceالمعجم الكبير للطبراني / مسند من يعرف بالكنى / 18945