Muwatta Malik, Book 42, Hadith 1547 (In-Book)

Yahya related to me from Malik from a reliable source from Bukayr ibn Abdullah ibn al-Ashajj from Abd ar-Rahman ibn al-Hubab al-Ansari from Abu Qatada al-Ansari that the Messenger of Allah, may Allah bless him and grant him peace, forbade making nabidh from dates and raisins together, and nearly ripe dates and fresh dates together. Malik said, "That is the way of doing things among us in which the people of knowledge in our city continue. It is disapproved of because the Messenger of Allah, may Allah bless him and grant him peace, forbade it."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ الثِّقَةِ، عِنْدَهُ عَنْ بُكَيْرِ بْنِ عَبْدِ اللَّهِ بْنِ الأَشَجِّ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْحُبَابِ الأَنْصَارِيِّ، عَنْ أَبِي قَتَادَةَ الأَنْصَارِيِّ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم نَهَى أَنْ يُشْرَبَ التَّمْرُ وَالزَّبِيبُ جَمِيعًا وَالزَّهْوُ وَالرُّطَبُ جَمِيعًا ‏.‏

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also referenced under: Book 42, Hadith 8 (USC-MSA)