Sahih Muslim 1080
صحيح مسلم#1080Sahihوَحَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا إِسْمَاعِيلُ، عَنْ أَيُّوبَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، - رضى الله عنهما - قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِنَّمَا الشَّهْرُ تِسْعٌ وَعِشْرُونَ فَلاَ تَصُومُوا حَتَّى تَرَوْهُ وَلاَ تُفْطِرُوا حَتَّى تَرَوْهُ فَإِنْ غُمَّ عَلَيْكُمْ فَاقْدِرُوا لَهُ " .
Ibn'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 do not fast till you have sighted it (the new moon) and do not break fast, till you have sighted it (the new moon of Shawwal), and if the sky is cloudy for you, then calculate
Scholarly Authentication
The label above is the grade most of these scholars gave, each scholar counted once — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. When they judged only its chain of narrators (“Isnaad”), the label says “Sound chain”. Each scholar's own wording:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
Sahih Muslim 1080 is the standard (Abd al-Baqi) number; this narration is #2502 in the MuslimGPT index.
In-book reference: 13:8