Abu al-Fadl Al-‘Abbās ibn ‘Abd al-Muttalib (may Allah be pleased with him) reported: I witnessed the Day of Hunayn with the Messenger of Allah (may Allah's peace and blessings be upon him). Abu Sufyān ibn al-Hārith ibn ‘Abd al-Muttalib and I stuck with the Messenger of Allah (may Allah's peace and blessings be upon him) and we did not leave him. The Messenger of Allah (may Allah's peace and blessings be upon him) was riding on his white mule. When the Muslims met the disbelievers on the battlefield, the Muslims retreated, but the Messenger of Allah (may Allah's peace and blessings be upon him) began to spur his mule on towards the disbelievers. I was holding onto the Messenger’s mule’s bridle (may Allah's peace and blessings be upon him) restraining it from going very fast. Abu Sufyān who was holding the Messenger’s mule’s stirrup (may Allah's peace and blessings be upon him) said: "O Al-‘Abbās, call out to the people of Samurah." Al-‘Abbās (who was a man with a loud voice) called out at the top of his voice: "Where are the people of Samurah?" Al-‘Abbās said: "And by Allah, when they heard my voice, they came back (to us) as cows come back to their calves, and they said: 'We are here, we are here!'" Al-‘Abbās said: “They began to fight the disbelievers. Then there was a call to the Ansār. Those (who called out to them) shouted: ‘O you people of the Ansār!' O people of the Ansār!‘ Banu al-Hārith ibn al-Khazraj were the last to be called. The Messenger of Allah (may Allah's peace and blessings be upon him) who was riding on his mule watched at their fight, stretched his neck forward, and said: ‘This is the time when the fight is raging hot.' Then the Messenger of Allah (may Allah's peace and blessings be upon him) took (some) pebbles and threw them in the faces of the disbelievers and said: ‘By the Lord of Muhammad, they are defeated.'" Al-‘Abbās said: “I went round and saw that the battle was in the same condition that I had seen it. And, by Allah! It remained in that same condition until he threw the pebbles. I continued to watch until I saw that their force had faded and they began to retreat."
Authentic hadith -
Narrated by Muslim