Sahih Muslim 4231

وحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، وَأَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، وَاللَّفْظُ لِيَحْيَى، قَالَ: أَخْبَرَنَا إِسْمَاعِيلُ ابْنُ عُلَيَّةَ، عَنِ ابْنِ عَوْنٍ، عَنْ إِبْرَاهِيمَ، عَنِ الْأَسْوَدِ بْنِ يَزِيدَ، قَالَ: ذَكَرُوا عِنْدَ عَائِشَةَ أَنَّ عَلِيًّا كَانَ وَصِيًّا، فَقَالَتْ: مَتَى أَوْصَى إِلَيْهِ؟ فَقَدْ كُنْتُ مُسْنِدَتَهُ إِلَى صَدْرِي - أَوْ قَالَتْ: حَجْرِي - فَدَعَا بِالطَّسْتِ، فَلَقَدِ انْخَنَثَ فِي حَجْرِي، وَمَا شَعَرْتُ أَنَّهُ مَاتَ، فَمَتَى أَوْصَى إِلَيْهِ

Aswad b. Yazid reported: It was mentioned before A'isha that will had been made (by the Holy Prophet) in favour of 'Ali (as the Prophet's first caliph), whereupon she said: When did he make will in his favour? I had been providing support to him (to the Holy Prophet) with my chest (or with my lap). He asked for a tray, when he fell in my lap (relaxing his body), and I did not realise that he had breathed his last. When did he make any will in his ('Ali's) favour?