Bayan Al-Hadith › Sahih Muslim › The Book of Fasting
Sahih Muslim 1080fصحيح مسلم 1080f
وَحَدَّثَنِي حُمَيْدُ بْنُ مَسْعَدَةَ الْبَاهِلِيُّ، حَدَّثَنَا بِشْرُ بْنُ الْمُفَضَّلِ، حَدَّثَنَا سَلَمَةُ، - وَهُوَ ابْنُ عَلْقَمَةَ - عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، - رضى الله عنهما - قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " الشَّهْرُ تِسْعٌ وَعِشْرُونَ فَإِذَا رَأَيْتُمُ الْهِلاَلَ فَصُومُوا وَإِذَا رَأَيْتُمُوهُ فَأَفْطِرُوا فَإِنْ غُمَّ عَلَيْكُمْ فَاقْدِرُوا لَهُ " .
'Abdullah b. 'Umar (Allah be pleased with both of them) reported Allah's Messenger (ﷺ) as saying: The month (of Ramadan) may consist of twenty nine days; so when you see the new moon observe fast and when you see (the new moon again at the commencement of the month of Shawwal) then break It, and if the sky is cloudy for you, then calculate it (and complete thirty days).
Grading
Sahih (authentic by the consensus of hadith scholars)
Chain of narrators
حميد بن مسعدة بن المبارك ← بشر بن المفضل بن لاحق ← سلمة بن علقمة ← نافع ← عبد الله بن عمر
Humayd ibn Mas'ada ibn al-Mubarak → Bishr ibn al-Mufaddal ibn Lahiq → Salama ibn Alqama → Nafi' → Ibn `Umar