Abu Huraira reported:
The Messenger of Allah (ﷺ) said: I have been helped by terror (in the heart of the enemy) ; I have been given words which are concise but comprehensive in meaning; and while I was asleep I was brought the keys of the treasures of the earth which were placed in my hand.
Reference: Sahih Muslim 523 e
In-book reference: Book 5, Hadith 11
USC-MSA web (English) reference(deprecated numbering scheme): Book 4, Hadith 1066