Sahih Bukhari Volume 006, Book 060, Hadith Number 106.
Narrated By Abdullah bin Masud : Allah's Apostle said to me, "Recite (of the Qur'an) for me," I said, "Shall I recite it to you although it had been revealed to you?" He said, "I like to hear (the Qur'an) from others." So I recited Surat-an-Nisa' till I reached: "How (will it be) then when We bring from each nation a witness, and We bring you (O Muhammad) as a witness against these people?" (4.41) Then he said, "Stop!" And behold, his eyes were overflowing with tears."