Sahih Bukhari
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
Volume: 005 / Book Number: 059 / Hadith Number: 289
Narrated Ibn Abbas:
On the day of the battle of Badr, the Prophet said, "O Allah! I appeal to You (to fulfill) Your Covenant and Promise. O Allah! If Your Will is that none should worship You (then give victory to the pagans)." Then Abu Bakr took hold of him by the hand and said, "This is sufficient for you." The Prophet came out saying, "Their multitude will be put to flight and they will show their backs." (54.45)