Sayyiduna Abu Hurayrah (may Allah be pleased with him) used to say: A brother of yours did not speak obscenity, meaning Sayyiduna Abdullah bin Rawahah (may Allah be pleased with him). He said: "Among us is the Messenger of Allah, reciting His Book, when the familiar light of dawn breaks forth, shining. He brought us guidance after blindness, so our hearts are certain of it, that whatever he said is true."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14031