Al-Kāfi - Volume 4 > The Time of Breaking Fast after Sunset
Hadith #1

1ـ عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ سَهْلِ بْنِ زِيَادٍ عَنْ مُحَمَّدِ بْنِ عِيسَى بْنِ عُبَيْدٍ عَنِ ابْنِ أَبِي عُمَيْرٍ عَمَّنْ ذَكَرَهُ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ السَّلاَم) قَالَ وَقْتُ سُقُوطِ الْقُرْصِ وَوُجُوبِ الإِفْطَارِ مِنَ الصِّيَامِ أَنْ يَقُومَ بِحِذَاءِ الْقِبْلَةِ وَيَتَفَقَّدَ الْحُمْرَةَ الَّتِي تَرْتَفِعُ مِنَ الْمَشْرِقِ فَإِذَا جَازَتْ قِمَّةَ الرَّأْسِ إِلَى نَاحِيَةِ الْمَغْرِبِ فَقَدْ وَجَبَ الإِفْطَارُ وَسَقَطَ الْقُرْصُ.

1. A number of our people have narrated from Sahl ibn Ziyad from Muhammad ibn ‘Isa ibn ‘Ubayd from ibn abu ‘Umayr from those whom he has mentioned who has said the following: “Abu ‘ Abd Allah, ‘Alayhi al-Salam, has said, ‘At the time of the fall of the disc (sunset) and obligatory breakfast, one can stand in front of al-Qiblah (al-Ka‘bah) and look for the redness that rises from the east. When it (redness) passes overhead toward the west, breaking fast becomes obligatory and the disk has fallen (it is sunset).’”