Sahih Bukhari Volume 004, Book 056, Hadith Number 710.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 56. Virtues and Merits of the Prophets (PBUH) and his Companions
Narated By Salama : Allah's Apostle passed by some people from the tribe of Aslam practicing archery. He said, "O children of Ishmael! Throw (arrows), for your father was an archer. I am on the side of Bani so-and-so," meaning one of the two teams. The other team stopped throwing, whereupon the Prophet said, "What has happened to them?" They replied, "How shall we throw while you are with Bani so-and-so?" He said, "Throw for I am with all of you."