حَدَّثَنَا يَحْيَی بْنُ بُکَيْرٍ قَالَ حَدَّثَنِي اللَّيْثُ عَنْ عُقَيْلٍ عَنْ ابْنِ شِهَابٍ قَالَ أَخْبَرَنِي سَالِمُ بْنُ عَبْدِ اللَّهِ بْنِ عُمَرَ أَنَّ ابْنَ عُمَرَ رَضِيَ اللَّهُ عَنْهُمَا قَالَ سَمِعْتُ رَسُولَ اللَّه صَلَّی اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ إِذَا رَأَيْتُمُوهُ فَصُومُوا وَإِذَا رَأَيْتُمُوهُ فَأَفْطِرُوا فَإِنْ غُمَّ عَلَيْکُمْ فَاقْدُرُوا لَهُ وَقَالَ غَيْرُهُ عَنْ اللَّيْثِ حَدَّثَنِي عُقَيْلٌ وَيُونُسُ لِهِلَالِ رَمَضَانَ
صحیح بخاری · Hadith 1900
Narrated Ibn `Umar: I heard Allah's Apostle saying, "When you see the crescent (of the month of Ramadan), start fasting, and when you see the crescent (of the month of Shawwal), stop fasting; and if the sky is overcast (and you can't see it) then regard the month of Ramadan as of 30 days."
Translated by Dr. Muhammad Muhsin Khan · Reviewed by Islamic University of Madinah · Published March 2020