I said to Anas, "Tell me, was the name 'Ansar' a name you used to call yourselves, or did Allah name you so?"He replied, "Rather, Allah named us."
قلت لأنس: أرأيت اسم الأنصار كنتم تسمون به، أم سماكم الله؟ قال: بل سمانا الله.
Bukhari related it in "Merits of the Ansar" (3776), from Musa bin Ismail, who said, Mahdi bin Maymun narrated to us, who said, Ghaylan bin Jareer narrated to us, who said, "I said to Anas," and then he related it.