Allah, exalted be He, says in Sūrat Āl ʿImrān (1): “There has already been for you a sign in the two hosts that met: one host fighting in the path of Allah and the other disbelieving. They saw them to be twice their own number with their very eyes, and Allah strengthens with His help whom He wills.”
According to the soundest of the two interpretations, the meaning is that the disbelieving force saw the believing force as twice the number of the disbelievers themselves—this, too, being the correct view—and that took place when the clash of arms and sword-play had begun in earnest (2). Allah cast weakness and terror into the hearts of the unbelievers: first He enticed them by showing the believers as few when the armies initially faced one another; then He supported the believers with His victory, making them appear in the eyes of the disbelievers as double their own number, until the latter lost heart, weakened, and were defeated. Hence His statement: “And Allah strengthens with His victory whom He wills; surely in that is a lesson for those endowed with insight.”
Israʾīl (3) reports, through Abū Isḥāq, from Abū ʿUbaydah (4), from ʿAbd Allah: “They were made to seem few in our eyes on the Day of Badr, so much so that I said to the man beside me, ‘Do you think they are seventy?’ He replied, ‘I think they are a hundred.’”
Ibn Isḥāq (5) said: My father, Isḥāq ibn Yasār, and others among the scholars related to me—on the authority of elders from the Anṣār—that when the enemy had settled in their camp they sent ʿUmayr ibn Wahb al-Jumaḥī, saying, “Estimate for us the number of Muhammad’s companions.” He rode his horse round the encampment, then returned and said, “They are three hundred men, a little more or a little less. But give me time so that I may see whether they have an ambush or reinforcements.” He then went far down the valley but saw nothing, came back, and said, “I saw nothing. Yet I have seen, O people of Quraysh, calamities bearing death; the water-camels of Yathrib are bringing lethal ruin. They are a people with no protection or refuge save their swords. By Allah, I do not think a single man of them will be slain until he has killed one of you; and if they take from you numbers equal to themselves, what value will life have thereafter? So decide what you will.”
When Ḥakīm ibn Ḥizām heard this he went among the people and came to ʿUtbah ibn Rabīʿah, saying, “Abū al-Walīd, you are the elder and leader of Quraysh, the one obeyed among them. Would you like to be remembered for good among them until the end of time?” He asked, “And what is that, O Ḥakīm?” He replied, “Turn the people back and take responsibility for your ally ʿAmr ibn al-Ḥaḍramī.” He said, “I have done so, and you are my guarantor in the matter. He is only my ally; I am liable for his blood-money and whatever of his property has been lost. Now go to the son of al-Ḥanẓaliyyah (8)—meaning Abū Jahl—for I fear no one but him may stir up the people.”
ʿUtbah then rose to address them and said, “O assembly of Quraysh, by Allah you will gain nothing by meeting Muhammad and his companions in battle. By Allah, if you kill him, a man will ever after have to look upon the face of another man whose sight he detests—killed….”