Narrated Ibn Ka'b b. Malik:

On the authority of his father: Umm Mubashshir said to the Prophet ﷺ during the sickness of which he died: What do you think about your illness, Messenger of Allah ﷺ? I do not think about the illness of my son except the poisoned sheep of which he had eaten with you at Khaybar. The Prophet ﷺ said: And I do not think about my illness except that. This is the time when it cut off my aorta.

Abu Dawud said: Sometime 'Abd al-Razzaq transmitted this tradition, omitting the link of the Companion, from Ma'mar, from al-Zuhri, from the Prophet ﷺ, and sometimes he transmitted it from al-Zuhri from 'Abd al-Rahman b. Ka'b b. Malik, 'Abd al-Rahman mentioned that Ma'mar sometimes transmitted the tradition in a mursal form (omitting the link of the Companion), and they recorded it. And all this is correct with us. 'Abd al-Razzaq said: When Ibn al-Mubarak came to Ma'mar, he transmitted the traditions in a musnad form (with a perfect chain) which he transmitted as mauquf traditions (statements of the Companions and not of the Prophet).

حَدَّثَنَا مَخْلَدُ بْنُ خَالِدٍ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، حَدَّثَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنِ ابْنِ كَعْبِ بْنِ مَالِكٍ، عَنْ أَبِيهِ، أَنَّ أُمَّ مُبَشِّرٍ، قَالَتْ لِلنَّبِيِّ ﷺ فِي مَرَضِهِ الَّذِي مَاتَ فِيهِ مَا يُتَّهَمُ بِكَ يَا رَسُولَ اللَّهِ فَإِنِّي لاَ أَتَّهِمُ بِابْنِي شَيْئًا إِلاَّ الشَّاةَ الْمَسْمُومَةَ الَّتِي أَكَلَ مَعَكَ بِخَيْبَرَ . وَقَالَ النَّبِيُّ ﷺ " وَأَنَا لاَ أَتَّهِمُ بِنَفْسِي إِلاَّ ذَلِكَ فَهَذَا أَوَانُ قَطَعَتْ أَبْهَرِي " . قَالَ أَبُو دَاوُدَ وَرُبَّمَا حَدَّثَ عَبْدُ الرَّزَّاقِ بِهَذَا الْحَدِيثِ مُرْسَلاً عَنْ مَعْمَرٍ عَنِ الزُّهْرِيِّ عَنِ النَّبِيِّ ﷺ وَرُبَّمَا حَدَّثَ بِهِ عَنِ الزُّهْرِيِّ عَنْ عَبْدِ الرَّحْمَنِ بْنِ كَعْبِ بْنِ مَالِكٍ وَذَكَرَ عَبْدُ الرَّزَّاقِ أَنَّ مَعْمَرًا كَانَ يُحَدِّثُهُمْ بِالْحَدِيثِ مَرَّةً مُرْسَلاً فَيَكْتُبُونَهُ وَيُحَدِّثُهُمْ مَرَّةً بِهِ فَيُسْنِدُهُ فَيَكْتُبُونَهُ وَكُلٌّ صَحِيحٌ عِنْدَنَا قَالَ عَبْدُ الرَّزَّاقِ فَلَمَّا قَدِمَ ابْنُ الْمُبَارَكِ عَلَى مَعْمَرٍ أَسْنَدَ لَهُ مَعْمَرٌ أَحَادِيثَ كَانَ يُوقِفُهَا .