Musnad Abu Ya'la al-Mawsili 117:8

'Abd al-A'la ibn Hammad narrated to us, Hammad narrated to us, from Thabit, from Anas ibn Malik, that the Messenger of Allah (ﷺ) fasted continuously (without breaking his fast) in Ramadan, so some of his companions also fasted continuously. He said: "If the month were extended for me, I would have fasted continuously in a way that those who go to extremes would abandon their extremism. I spend the day while my Lord feeds me and gives me to drink."