On the day of the battle of the Trench, the Prophet (ﷺ) wanted somebody from amongst the people to
volunteer to be a reconnoitre. Az-Zubair volunteered. He demanded the same again and Az-Zubair
volunteered again. Then he repeated the same demand (thrice) and AzZubair volunteered once more.
The Prophet (ﷺ) then said, " Every prophet has a disciple and my disciple is Az-Zubair."
Sahih al-Bukhari Book 56, Hadith 206