Musnad Abu Ya'la al-Mawsili 128:2

Muhammad ibn Abdullah ibn Numayr narrated to us, Abu Mu'awiyah narrated to us, from al-A'mash, from Abu Sufyan, from Anas ibn Malik, who said: Gabriel, peace be upon him, came to the Prophet, may Allah bless him and grant him peace, one day while he was sad, sitting, for some of the people of Makkah had struck him. He said: "They did to me such and such, and they did such and such." He [Gabriel] said: "Would you like me to show you a sign?" He looked at a tree behind the valley and said: "Call that tree." So he called it, and it came walking until it stood before him. He said to it: "Return," so it returned until it went back to its place. The Prophet, may Allah bless him and grant him peace, said: "It is sufficient for me."