Musnad Abu Ya'la al-Mawsili 152:92

Abu Khaythama narrated to us, Jarir narrated to us, from al-A'mash, from Ibrahim, from 'Alqama, from 'Abdullah, who said: A man from the People of the Scripture came to the Messenger of Allah (may Allah bless him and grant him peace) and said: "Indeed, Allah holds the heavens upon a finger, the earths upon a finger, the mountains and the trees upon a finger, the water and the soil upon a finger, and all of creation upon a finger. Then He says: 'I am the King.'" So the Messenger of Allah (may Allah bless him and grant him peace) laughed until his molars appeared. Then he recited this verse: "And they have not appraised Allah with true appraisal, while the earth entirely will be His grip on the Day of Resurrection, and the heavens will be folded in His right hand." I said to Ibrahim: "Is it in this world or in the Hereafter?" He said: "In this world."