It is narrated from Sayyiduna Abdullah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said to him: "Recite." So he began Surah al-Nisa', until, when he reached this verse: "So how will it be when We bring from every nation a witness, and bring you (O Prophet) as a witness over these?" [Surah al-Nisa': 41], his (peace and blessings be upon him) eyes flowed with tears and he said: "Stop; that is enough for us."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8427