Sahih Bukhari Volume 005, Book 058, Hadith Number 137.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 58. Merits of the Helpers in Madina (Ansaar)
Narated By Anas bin Malik : The Prophet said to the Ansar, "After me you will see others given preference to you; so be patient till you meet me, and your promised place (of meeting) will be the Tank (i.e. Lake of Kauthar)."