Muwatta Malik, Book 28, Hadith 14 (USC-MSA)

Yahya related to me from Malik from Abdullah ibn Abi Bakr ibn Muhammad ibn Amr ibn Hazm from Abd al-Malik ibn Abi Bakr ibn Abd ar- Rahman ibn al-Harith ibn Hisham al-Makhzumi from his father that when the Messenger of Allah, may Allah bless him and grant him peace, married Umm Salama and then spent the night with her, he said to her, "You are not being humbled in your right. If you wish, I will stay with you for seven nights as I stayed seven nights with the others. If you wish, I will stay with you for three nights, and then visit the others in turn." She said, "Stay three nights."

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ عَبْدِ اللَّهِ بْنِ أَبِي بَكْرِ بْنِ مُحَمَّدِ بْنِ عَمْرِو بْنِ حَزْمٍ، عَنْ عَبْدِ الْمَلِكِ بْنِ أَبِي بَكْرِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ الْحَارِثِ بْنِ هِشَامٍ الْمَخْزُومِيِّ، عَنْ أَبِيهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم حِينَ تَزَوَّجَ أُمَّ سَلَمَةَ وَأَصْبَحَتْ عِنْدَهُ قَالَ لَهَا ‏ "‏ لَيْسَ بِكِ عَلَى أَهْلِكِ هَوَانٌ إِنْ شِئْتِ سَبَّعْتُ عِنْدَكِ وَسَبَّعْتُ عِنْدَهُنَّ وَإِنْ شِئْتِ ثَلَّثْتُ عِنْدَكِ وَدُرْتُ ‏" ‏ ‏.‏ فَقَالَتْ ثَلِّثْ ‏.‏

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also referenced under: Book 28, Hadith 1108 (In-Book)