Al-Kāfi
Hadith 2976ـ أَحْمَدُ عَنْ عَلِيِّ بْنِ الْحَكَمِ عَنْ أَبِي أَيُّوبَ الْخَزَّازِ عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ عَنْ أَبِي جَعْفَرٍ (عَلَيْهِ السَّلاَم) قَالَ إِذَا رَأَيْتُمُ الْهِلالَ فَصُومُوا وَإِذَا رَأَيْتُمُوهُ فَأَفْطِرُوا وَلَيْسَ بِالرَّأْيِ وَلا بِالتَّظَنِّي وَلَيْسَ الرُّؤْيَةَ أَنْ يَقُومَ عَشَرَةُ نَفَرٍ فَيَقُولَ وَاحِدٌ هُوَ ذَا وَيَنْظُرُ تِسْعَةٌ فَلا يَرَوْنَهُ لَكِنْ إِذَا رَآهُ وَاحِدٌ رَآهُ أَلْفٌ.
6. Ahmad has narrated from Ali ibn al-Hakam from abu Ayyub al-Khazzaz from Muhammad ibn Muslim who has said the following: “Abu Ja’far (a.s.), has said, ‘When you see the crescent, then fast and when you see the crescent (again), then discontinue fasting. It is not by opinions and conjectures. If out of ten people only one says that there is the crescent but the rest cannot see, it is not seeing. If one can see a thousand can also see.’”