In Ramadhan of the second year after the Hijrah, the great battle of Badr took place. Its immediate cause was that the Prophet (Peace and blessings of Allah upon him) went out with 313 men to intercept a large caravan of the Quraysh that was on its way back from Syria. Abu Sufyan(may Allah be pleased with them), the caravan's leader, was extremely alert and cautious. He would ask everyone he met about the Muslims' movements. He learned of their departure from Madinah when near the town of Badr, so he turned the caravan toward the west to take the coastal route and avoid the dangerous road to Badr. He sent a man ahead to inform the people of Makkah that their properties were in danger and that the Muslims had prepared to attack the caravan.
When the Makkans heard this, they arose to come to the aid of Abu Sufyan(may Allah be pleased with them). None of their chiefs remained behind except Abu Lahab; and they gathered the neighbouring tribes, none of them remaining behind except the clan of `Adiyy.
When the army reached Juhfah they learned that Abu Sufyan had escaped harm and that he had told them to return to Makkah. They were set to return but Abu Jahl encouraged them to go ahead and fight. Three hundred men from Bani Zahrah returned and the rest, a thousand men, continued their march. They camped outside Badr in an open space behind the hills surrounding the town.
The Messenger of Allah (Peace and blessings of Allah upon him) consulted his companions and found that they were willing and determined to fight and sacrifice for the cause of Allah(Almighty). This pleased him and he (Peace and blessings of Allah upon him) said,
"Proceed and receive good tidings, for Allah, the Exalted, Has promised me one of the two parties. By Allah, it is as if I am now observing those peoples' demise."
The Prophet (Peace and blessings of Allah upon him) advanced and camped close to the nearer side of Badr. Al-Hubab ibn al-Mundhir(may Allah be pleased with them)advised him to advance and camp at the nearest well to the enemy so that the Muslims could collect water in containers for themselves and then fill the remaining wells with sand so the enemy would have no water. The Prophet (Peace and blessings of Allah upon him) did what Hubab(may Allah be pleased with them) advised.
The Prophet (Peace and blessings of Allah upon him) spent the eve of the battle, Friday, the 17th of Ramadhan, standing in prayer, weeping and supplicating Allah(Almighty) to support him against his enemies. `Ali ibn Abi Talib (may Allah be pleased with them) said, "I saw that everyone was asleep except for the Messenger of Allah (Peace and blessings of Allah upon him), who prayed under a tree and wept until the morning." (Ahmad)
`Ali (may Allah be pleased with them) also reported: "We were touched by a sprinkle of rain [the eve of Badr] so we sought cover under trees and leather shields. The Messenger of Allah (Peace and blessings of Allah upon him) spent the night supplicating his Lord and saying, "If this small band is destroyed You will not be worshipped." When dawn had broken he (Peace and blessings of Allah upon him) called, "Prayer, O servants of Allah!" The people came out from under the trees and shields and the Messenger of Allah (Peace and blessings of Allah upon him) led us in prayer and encouraged us to fight. (Ahmad)
Allah(Almighty) supported His Prophet (Peace and blessings of Allah upon him) and the believers with help and soldiers from Him. He(Almighty) said in the Qur'an: [Remember] when you asked help of your Lord, and He answered you, "Indeed, I will reinforce you with a thousand of the angels, following one another." And Allah made it not but good tidings and so your hearts would be assured thereby. And victory is not but from Allah. Indeed, Allah is Exalted in Might and Wise. (8:9-10) And He said: And Allah gave you victory at Badr while you were few. (3:123)
He also said: And you did not kill them, but it was Allah who killed them. And you threw not, [O Muhammad], when you threw, but it was Allah who threw. (8:17)
The battle began with a duel, and Hamzah (may Allah be pleased with them) killed Shaybah ibn Rabi`ah and `Ali(may Allah be pleased with them) killed al-Waleed ibn `Utbah. `Utbah ibn Rabi`ah was injured from the side of the polytheists and `Ubaydah ibn al-Harith was injured from the side of the Muslims.
The battle then began and became intense, and there was fierce fighting. Allah(Almighty) reinforced the Muslims with companies of angels to fight beside them and keep their hearts firm. Within an hour the polytheists were defeated and were fleeing. The Muslims pursued them, killing some and taking others prisoner. Seventy of the Polytheists were killed; among them were `Utbah, Shaybah, al-Waleed ibn `Utbah, Umayyah ibn Khalaf and his son, `Ali, Handhalah ibn Abi Sufyan and Abu Jahl ibn Hisham. Another seventy were taken prisoner.
Among the results of the battle of Badr was that the Muslims were strengthened and were now feared in Madinah and the adjacent areas. Their trust in Allah(Almighty) was increased and they perceived that Allah(Almighty) supports His believing servants, although a minority, against disbelievers, who might be a majority. The Muslims acquired fighting skills and learned new manoeuvres, strategies and methods of siege to deprive the enemy of means to continue warfare.