Musnad Abu Ya'la al-Mawsili 117:149

Abu Bakr ibn Abi Shaybah narrated to us, Waki' narrated to us, from Hammad ibn Salamah, from Thabit, from Anas, who said: The Messenger of Allah (ﷺ) said: "I have been harmed for the sake of Allah, and no one is harmed [like that]. And I have been made to fear for the sake of Allah, and no one is made to fear [like that]. And there came upon me three days and nights, during which neither I nor Bilal had any food except what Bilal’s armpit could conceal."