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bukhari:5604al-Ḥumaydī > Sufyān > Sālim Abū al-Naḍr > ʿUmayr a freed slave of Um al-Faḍl > Um al-Faḍl

The people doubted whether Messenger of Allah ﷺ was fasting or the Day of ʿArafat or not. So I sent a cup containing milk to him and he drank it.  

البخاري:٥٦٠٤حَدَّثَنَا الْحُمَيْدِيُّ سَمِعَ سُفْيَانَ أَخْبَرَنَا سَالِمٌ أَبُو النَّضْرِ أَنَّهُ سَمِعَ عُمَيْرًا مَوْلَى أُمِّ الْفَضْلِ يُحَدِّثُ عَنْ أُمِّ الْفَضْلِ قَالَتْ

شَكَّ النَّاسُ فِي صِيَامِ رَسُولِ اللَّهِ ﷺ يَوْمَ عَرَفَةَ فَأَرْسَلْتُ إِلَيْهِ بِإِنَاءٍ فِيهِ لَبَنٌ فَشَرِبَ فَكَانَ سُفْيَانُ رُبَّمَا قَالَ شَكَّ النَّاسُ فِي صِيَامِ رَسُولِ اللَّهِ ﷺ يَوْمَ عَرَفَةَ فَأَرْسَلَتْ إِلَيْهِ أُمُّ الْفَضْلِ فَإِذَا وُقِفَ عَلَيْهِ قَالَ هُوَ عَنْ أُمِّ الْفَضْلِ