صحيح مسلم
Sahih Muslim
كتاب الصيام
The Book of Fasting
باب بَيَانِ أَنَّ الدُّخُولَ فِي الصَّوْمِ يَحْصُلُ بِطُلُوعِ الْفَجْرِ وَأَنَّ لَهُ الأَكْلَ وَغَيْرَهُ حَتَّى يَطْلُعَ الْفَجْرُ وَبَيَانِ صِفَةِ الْفَجْرِ الَّذِي تَتَعَلَّقُ بِهِ الأَحْكَامُ مِنَ الدُّخُولِ فِي الصَّوْمِ وَدُخُولِ وَقْتِ صَلاَةِ الصُّبْحِ وَغَيْرِ ذَلِكَ:
Chapter: Clarifying that fasting begins at dawn, and a person may eat and other than that until dawn begins; And clarifying the dawn which has to do with the rulings concerning the beginning of fasting and the beginning of the time for the Subh Prayer, and other than that, which is the Second Dawn, which is called the True Dawn. The First Dawn, which is the False Dawn, has nothing to do with the rulings
Hadith 1092
This hadith is listed as number 2536 in Maktaba Shamila
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى ، وَمُحَمَّدُ بْنُ رُمْحٍ ، قَالَا : أَخْبَرَنَا اللَّيْثُ . ح وحَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ ، حَدَّثَنَا لَيْثٌ ، عَنْ ابْنِ شِهَابٍ ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ ، عَنْ عَبْدِ اللَّهِ رَضِيَ اللَّهُ عَنْهُ ، عَنْ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ، أَنَّهُ قَالَ : " إِنَّ بِلَالًا يُؤَذِّنُ بِلَيْلٍ ، فَكُلُوا وَاشْرَبُوا ، حَتَّى تَسْمَعُوا تَأْذِينَ ابْنِ أُمِّ مَكْتُومٍ " .
'Abdullah bin Mas'ud (RA) reported that the Messenger of Allah (ﷺ) had said: Bilal (RA) would pronounce Adhan (at the fag end of the night in order to inform the people about the time of the Sahri). So you eat and drink till you hear the Adhan of Ibn Umm Maktum (which was pronounced at the conclusion of the Sahri and the commencement of the fast).
