Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrated: A man from Banu Amir came to the Messenger of Allah (peace and blessings be upon him), and he used to practise healing. He said: O Muhammad, you say certain things; would you like me to treat you? The narrator said: So the Messenger of Allah (peace and blessings be upon him) invited him to Allah, the Mighty and Majestic, then said: "Would you like me to show you a sign?" There was a date palm and a tree near him. The Messenger of Allah (peace and blessings be upon him) called one of its branches, and it came towards him (peace and blessings be upon him), prostrating and raising its head, until it reached him (peace and blessings be upon him) and stood in front of him (peace and blessings be upon him). Then the Messenger of Allah (peace and blessings be upon him) said to it: "Go back to your place." So it returned to its place. The Amiri said: By Allah, I will never deny anything you say. Then he said: O Banu Sa'sa'ah, by Allah, I will never call anything he says a lie.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 12542