Musnad Abu Ya'la al-Mawsili 42:323

Zuhayr narrated to us, Yazid bin Harun narrated to us, Ibn Abi Dhi'b Muhammad bin Abd al-Rahman informed us, from al-Maqburi, from Abd al-Rahman bin Abi Sa'id, from his father, who said: We were detained on the day of the Trench from the Dhuhr, Asr, Maghrib, and Isha prayers until we were spared [from the fighting]. That is the saying of Allah: "And Allah spared the believers from the fighting, and Allah is Powerful, Exalted in Might." The Messenger of Allah (peace be upon him) stood up and ordered Bilal, so he performed the iqamah, then he prayed the Dhuhr as he used to pray it before that. Then he performed the iqamah and prayed the Asr as he used to pray it before that. Then he performed the iqamah for the Maghrib and prayed it as he used to pray it before that. Then he performed the iqamah for the Isha and prayed it as he used to pray it before that. And that was before the revelation of: "But if you fear, then [pray] on foot or riding."