Musnad Ahmad 30:2739

Hajjaj narrated to us, he said: Layth narrated to us, he said: Uqayl ibn Khalid narrated to me, from Ibn Shihab, from Sa'id ibn al-Musayyib, that Abu Hurayrah said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "I have been sent with the comprehensive words (jawami' al-kalim), and I have been aided by fear (al-ru'b). And while I was sleeping, I was brought the keys to the treasures of the earth, and they were placed in my hand."