Sahih MuslimChapter 13Hadith 2516
Full Sharh — Sahih Muslim 2516
وَحَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا شُعْبَةُ، عَنْ مُحَمَّدِ بْنِ زِيَادٍ، قَالَ سَمِعْتُ أَبَا هُرَيْرَةَ، - رضى الله عنه - يَقُولُ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " صُومُوا لِرُؤْيَتِهِ وَأَفْطِرُوا لِرُؤْيَتِهِ فَإِنْ غُمِّيَ عَلَيْكُمُ الشَّهْرُ فَعُدُّوا ثَلاَثِينَ " .
English Translation
Abu Huraira reported Allah's Messenger (ﷺ) as saying:Observe fast on sighting it (the new moon) and break it on sighting it. But if (due to clouds) the actual position of the month is concealed from you, you should then count thirty (days)
Source
Sahih Muslim(صحيح مسلم)
The Book of Fasting
Hadith Number
2516