Musnad Abu Ya'la al-Mawsili 109:129

Ishaq narrated to us, Abd al-Warith ibn Sa'id narrated to us, al-Qasim ibn Abd al-Wahid narrated to us, from Abdullah ibn Muhammad ibn Aqil, from Jabir, from the Prophet, may Allah bless him and grant him peace, who said: "Indeed, the thing I fear most for my nation after me is the deed of the people of Lot."