Jami` at-Tirmidhi, Book 47, Hadith 3233 (In-Book) ⓘ
Narrated 'Adi bin Hatim: "When 'Until the white (light) thread of dawn appears distinct to you from the black thread (of night)' was revealed, the Prophet said to me: 'That only refers to the whiteness of the day from the blackness of the night.'"
حَدَّثَنَا أَحْمَدُ بْنُ مَنِيعٍ، حَدَّثَنَا هُشَيْمٌ، أَخْبَرَنَا حُصَيْنٌ، عَنِ الشَّعْبِيِّ، أَخْبَرَنَا عَدِيُّ بْنُ حَاتِمٍ، قَالَ لَمَّا نَزَلَتْ : ( حَتَّى يَتَبَيَّنَ لَكُمُ الْخَيْطُ الأَبْيَضُ مِنَ الْخَيْطِ الأَسْوَدِ مِنَ الْفَجْرِ ) قَالَ لِي النَّبِيُّ صلى الله عليه وسلم " إِنَّمَا ذَاكَ بَيَاضُ النَّهَارِ مِنْ سَوَادِ اللَّيْلِ " . قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ .
also referenced under: Hadith 2970 (Reference) & Volume 5, Book 44, Hadith 2970 (DarusSalam)