Sahih Muslim Book 23, Hadith Number 5090.

Chapter : The merit of the fruit of Arak tree.

Jabir b. Abdullah reported: We were with the Apostle of Allah (may peace be upon him) at Marr az-Zahran, and we were plucking the fruit of the Arak tree, whereupon Allah’s Messenger (may peace he upon him) said: Pluck only its black ones (for they are the most pleasant). We said: Allah’s Messenger, it seems you shepherded the flock. He said: Yes. Has there been a prophet who did not shepherd it (or some words like it)?