30/11. Chapter:
"Start observing Saum on seeing the crescent of Ramadan, and stop on seeing the crescent (of Shawwal)."
And ‘Ammar said, “Whoever observes Saum (fasting) on a doubtful day is disobeying Abul-Qasim (i.e., the Prophet ﷺ).”
Sahih Bukhari : 1906
Sahih BukhariHadith Number 1906
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ ـ رضى الله عنهما ـ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم ذَكَرَ رَمَضَانَ فَقَالَ " لاَ تَصُومُوا حَتَّى تَرَوُا الْهِلاَلَ، وَلاَ تُفْطِرُوا حَتَّى تَرَوْهُ، فَإِنْ غُمَّ عَلَيْكُمْ فَاقْدُرُوا لَهُ ".
Narrated `Abdullah bin `Umar: Allah's Messenger (ﷺ) mentioned Ramadan and said, "Do not fast unless you see the crescent (of Ramadan), and do not give up fasting till you see the crescent (of Shawwal), but if the sky is overcast (if you cannot see it), then act on estimation (i.e. count Sha'ban as 30 days).
Reference : Sahih al-Bukhari 1906In-book reference : Book 30, Hadith 16USC-MSA web (English) reference : Vol. 3, Book 31, Hadith 130
