The Messenger of Allah ﷺ said, "I have been granted victory through awe, given the most concise yet comprehensive speech, and the earth has been made a place of prayer and a means of purification for me. While I was sleeping, the keys to the treasures of the earth were brought and placed in my hand."
حدثنا يزيد أخبرنا محمد بن عمرو عن أبي سلمة
قال رسول الله ﷺ نصرت بالرعب وأوتيت جوامع الكلم وجعلت لي الأرض مسجدا وطهورا وبينا أنا نائم أوتيت بمفاتيح خزائن الأرض فتلت في يدي
Its isnad is sahih. It was mentioned previously at 9115 in the printed edition.As for his saying, "it fell into my hand," the meaning is "it was surrendered to me," but its meaning is more emphatic than "surrendered." This is because the word "tall" originally means to throw something down and cast it on its face so that it submits to you. Accordingly, the meaning here is that Allah cast it down and it submitted, so He delivered it to the Messenger of Allah ﷺ.