Sa'id b. Jubair reported from Ibn Abbas that he said:

Thursday, and what about Thursday? Then tears began to flow until I saw them on his cheeks as it they were the strings of pearls. He (the narrator) said that Allah's Messenger (ﷺ) said: Bring me a shoulder blade and ink-pot (or tablet and inkpot), so that I write for you a document (by following which) you would never go astray. They said: Allah's Messenger (may peace upon him) is in the state of unconsciousness.
حَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، أَخْبَرَنَا وَكِيعٌ، عَنْ مَالِكِ بْنِ مِغْوَلٍ، عَنْ طَلْحَةَ بْنِ مُصَرِّفٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، أَنَّهُ قَالَ يَوْمُ الْخَمِيسِ وَمَا يَوْمُ الْخَمِيسِ ‏.‏ ثُمَّ جَعَلَ تَسِيلُ دُمُوعُهُ حَتَّى رَأَيْتُ عَلَى خَدَّيْهِ كَأَنَّهَا نِظَامُ اللُّؤْلُؤِ ‏.‏ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ ائْتُونِي بِالْكَتِفِ وَالدَّوَاةِ - أَوِ اللَّوْحِ وَالدَّوَاةِ - أَكْتُبْ لَكُمْ كِتَابًا لَنْ تَضِلُّوا بَعْدَهُ أَبَدًا ‏"‏ ‏.‏ فَقَالُوا إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم يَهْجُرُ ‏.‏
Reference : Sahih Muslim 1637 b
In-book reference : Book 25, Hadith 30
USC-MSA web (English) reference : Book 13, Hadith 4015
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