Sunan Ibn Majah
Sunan Ibn Majah 1654
حَدَّثَنَا أَبُو مَرْوَانَ، مُحَمَّدُ بْنُ عُثْمَانَ الْعُثْمَانِيُّ حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ، عَنِ الزُّهْرِيِّ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، عَنِ ابْنِ عُمَرَ، قَالَ: قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " إِذَا رَأَيْتُمُ الْهِلاَلَ فَصُومُوا وَإِذَا رَأَيْتُمُوهُ فَأَفْطِرُوا . فَإِنْ غُمَّ عَلَيْكُمْ فَاقْدُرُوا لَهُ " . وَكَانَ ابْنُ عُمَرَ يَصُومُ قَبْلَ الْهِلاَلِ بِيَوْمٍ .
Unreviewed translation. All hadiths in this collection are available in five languages. Titles and introductions may remain in Arabic.
Abu Marwan Muhammad ibn Uthman al-Uthmani narrated to us; Ibrahim ibn Sa‘d narrated to us, from al-Zuhri, from Salim ibn Abdullah, from Ibn Umar, who said: The Messenger of Allah (peace and blessings be upon him) said: ‘When you see the crescent, fast, and when you see it, break your fast. If it is obscured from you, then estimate it.’ Ibn Umar used to fast a day before the crescent.
Notes and open questions — unreviewed
‘Estimate it’ renders the source closely without specifying the method or what is being estimated.
The source separately attributes the practice of fasting a day before the crescent to Ibn Umar; it is retained as a distinct statement.
فَإِنْ غُمَّ عَلَيْكُمْ فَاقْدُرُوا لَهُ " .
The command فاقدروا له says to estimate it, but the object and method of estimation are not made explicit in this wording.
Does ‘estimate it’ preserve the source without supplying an unstated method?