Sayyiduna Anas bin Malik (may Allah be pleased with him) narrates: On the day of the Battle of the Trench, the Prophet (peace and blessings be upon him) was reciting these verses: "By Allah! Were it not for Allah, we would not have been guided, nor would we have fasted, nor would we have prayed. (O Allah!) Send down tranquillity upon us!"
Al-Bazzar and Abu Ya'la recorded it, and the narrators of both are thiqat (trustworthy).