Muwatta Malik, Book 20, Hadith 837 (In-Book)

Yahya related to me from Malik from Yahya ibn Said from al-Qasim ibn Muhammad that A'isha, umm al-muminin, used to fast on the day of Arafa. Al-Qasim said, "I saw her, when the imam began moving away (after sunset) on the afternoon of Arafa, stay where she was until the ground between her and the people became clear. Then she asked for something to drink and broke her fast."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنِ الْقَاسِمِ بْنِ مُحَمَّدٍ، أَنَّ عَائِشَةَ أُمَّ الْمُؤْمِنِينَ، كَانَتْ تَصُومُ يَوْمَ عَرَفَةَ ‏.‏ قَالَ الْقَاسِمُ وَلَقَدْ رَأَيْتُهَا عَشِيَّةَ عَرَفَةَ يَدْفَعُ الإِمَامُ ثُمَّ تَقِفُ حَتَّى يَبْيَضَّ مَا بَيْنَهَا وَبَيْنَ النَّاسِ مِنَ الأَرْضِ ثُمَّ تَدْعُو بِشَرَابٍ فَتُفْطِرُ ‏.‏

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also referenced under: Book 20, Hadith 134 (USC-MSA)