"The battle of Siffin between Ali bin Abu Talib and Muawiya broke out on 8th Safar, 36/July 26, 657. A fierce battle was fought between them on the whole day, and it even continued in the darkness of that night, which is known as lail at-harir (the night of clangour). William Muir writes in The Caliphate, its Rise and Fall (London, 1924, p. 261) that, "Both armies drawn out in entire array, fought till the shades of evening fell, neither having got the better. The following morning, the combat was renewed with great vigour. Ali posed himself in the centre with the flower of his troops from Medina, and the wings were formed, one of the warriors from Basra, the other of those from Kufa. Muawiya had a pavilion pitched on the field; and there, surrounded by five lines of his sworn body-guards, watched the day. Amr with a great weight of horse bore down upon the Kufa wing, which gave away; and Ali was exposed to imminent peril, both from thick showers of arrows and from close encounter. Reproaching the men of Kufa for their cowardice, the Caliph fought bravely, his unwieldy figure notwithstanding, sword in hand, and manfully withstood the charge. Ali's general Ashtar, at the head of 300 readers of (the Koran) led forward the other wing, which fell with fury on Muawiya's Turbaned body-guard. Four of its five ranks were cut to pieces, and Muawiya, bethinking himself of flight, had already called for his horse, when a martial couplet flashed in his mind, and he held his ground."
Imam Muhammad al-Bakir relates that when the lail at-harir came, both parties said that they would not leave the field till death or God grants them victory. They started fighting early in the morning on a day. It was a long hot day. They threw arrows at each other to the extent that there were no more arrows. They stabbed each other to the extent that the spears were broken. Then the people dismounted their horses. They advanced against each other. Then they hit each other to the extent that the swords were broken. Then, the knights fought against each other with swords and iron bars. So, the listeners heard nothing except the mumble of the people, the clashing of the swords at the field, and the biting of the mouths. Then the sun was eclipsed. The fighting was intense. So, during those critical moments, the old men shouted, "O'people of Arabia, fear God regarding the women and the girls." (The Life of Imam Muhammad al-Baqir by Baqir Sharif al-Qarashi, Qum, 1999, pp. 254-5).