Sahih Bukhari Volume 4, Book 52, Hadith Number 99.

Narated By Jabir : The Prophet said, “Who will bring me the information about the enemy on the day (of the battle) of Al-Ahzab (i.e. Clans)?” Az-Zubair said, “I will.” The Prophet said again, “Who will bring me the information about the enemy?” Az-Zubair said again, “I will.” The Prophet said, “Every prophet had a disciple and my disciple is Az-Zubair.”