Muwatta Malik, Book 8, Hadith 315 (In-Book)

Yahya related to me from Malik from Zayd ibn Aslam from al-Qaqa ibn Hakim that Abu Yunus, the mawla of A'isha, umm al-muminin said, ''A'isha ordered me to write out a Qur'an for her. She said, 'When you reach this ayat, let me know, "Guard the prayers carefully and the middle prayer and stand obedient to Allah." ' When I reached it I told her, and she dictated to me, 'Guard the prayers carefully and the middle prayer and the asr prayer and stand obedient to Allah.' A'isha said, 'I heard it from the Messenger of Allah, may Allah bless him and grant him peace.' "

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ زَيْدِ بْنِ أَسْلَمَ، عَنِ الْقَعْقَاعِ بْنِ حَكِيمٍ، عَنْ أَبِي يُونُسَ، مَوْلَى عَائِشَةَ أُمِّ الْمُؤْمِنِينَ أَنَّهُ قَالَ أَمَرَتْنِي عَائِشَةُ أَنْ أَكْتُبَ لَهَا مُصْحَفًا ثُمَّ قَالَتْ إِذَا بَلَغْتَ هَذِهِ الآيَةَ فَآذِنِّي ‏{‏حَافِظُوا عَلَى الصَّلَوَاتِ وَالصَّلاَةِ الْوُسْطَى وَقُومُوا لِلَّهِ قَانِتِينَ‏}‏ فَلَمَّا بَلَغْتُهَا آذَنْتُهَا فَأَمْلَتْ عَلَىَّ حَافِظُوا عَلَى الصَّلَوَاتِ وَالصَّلاَةِ الْوُسْطَى وَصَلاَةِ الْعَصْرِ وَقُومُوا لِلَّهِ قَانِتِينَ قَالَتْ عَائِشَةُ سَمِعْتُهَا مِنْ رَسُولِ اللَّهِ صلى الله عليه وسلم ‏.‏

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also referenced under: Book 8, Hadith 26 (USC-MSA)