Musnad Abu Ya'la al-Mawsili 107:8

Muhammad ibn Abd Allah ibn Numayr narrated to us, Bakr ibn Yunus ibn Bukayr narrated to us, from Musa ibn Ali, from his father, from Uqbah ibn Amir, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Do not force your sick ones to eat or drink, for indeed Allah feeds them and gives them drink."