Sahih Muslim Book - 13, Hadith - 2636

وَحَدَّثَنِى هَارُونُ بْنُ سَعِيدٍ الأَيْلِىُّ حَدَّثَنَا ابْنُ وَهْبٍ أَخْبَرَنِى عَمْرٌو عَنْ بُكَيْرِ بْنِ الأَشَجِّ عَنْ كُرَيْبٍ مَوْلَى ابْنِ عَبَّاسٍ - رضى الله عنهما - عَنْ مَيْمُونَةَ زَوْجِ النَّبِىِّ -صلى الله عليه وسلم- أَنَّهَا قَالَتْ إِنَّ النَّاسَ شَكُّوا فِى صِيَامِ رَسُولِ اللَّهِ -صلى الله عليه وسلم- يَوْمَ عَرَفَةَ فَأَرْسَلَتْ إِلَيْهِ مَيْمُونَةُ بِحِلاَبِ اللَّبَنِ وَهُوَ وَاقِفٌ فِى الْمَوْقِفِ فَشَرِبَ مِنْهُ وَالنَّاسُ يَنْظُرُونَ إِلَيْهِ.

It was narrated from Maimunah [may Allah be pleased with her], the wife of the Prophet (SAW) said: “The people were not sure whether the Messenger of Allah (SAW) was fasting on the Day of Arafah, so Maimunah sent him a vessel of milk, while he was standing in the Mawqif (place of standing), and he drank from it while the people were looking at him.”