Musannaf Ibn Abi Shayba 36:154

Abu Mu'awiyah narrated to us, he said: Al-A'mash narrated to us, from Abu Ishaq, from Zayd ibn Yuthay', he said: Abu Bakr was with the Messenger of Allah, may Allah bless him and grant him peace, on the day of Badr upon the canopy (al-'arish). He said: The Prophet, may Allah bless him and grant him peace, began to supplicate, saying: "O Allah, grant victory to this group, for if You do not do so, You will not be worshipped on the earth." Abu Bakr said: "Some of your pleading with your Lord [is enough], for by Allah, He will surely fulfill for you what He promised you."