Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) narrates: I was with the Messenger of Allah (peace and blessings be upon him) on the day of Hunayn. The people turned their backs and left him (peace and blessings be upon him), and I remained with him (peace and blessings be upon him) among eighty (80) men of the Muhajirun and the Ansar. We stepped back on our heels about eighty paces, but we did not turn our backs to them, and these are the ones upon whom Allah, the Mighty and Majestic, sent down tranquillity (sakinah). He said: the Messenger of Allah (peace and blessings be upon him) was pressing straight ahead on his mule; then his (peace and blessings be upon him) mule shied and he leaned somewhat from the saddle. I rushed towards him (peace and blessings be upon him) and said: "Rise up, may Allah raise you." He (peace and blessings be upon him) said: "Hand me a fistful of dust." Then he (peace and blessings be upon him) threw it at their (the enemy's) faces, and their eyes were filled with dust. He (peace and blessings be upon him) said: "Where are the Muhajirun and the Ansar?" I said: "They are right here." He (peace and blessings be upon him) said: "Call out to them." So I called out to them, and they came with their swords in their hands like shooting stars, and the polytheists turned their backs and fled.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10313