- وَ وَجَدْتُ مُثْبَتاً فِي بَعْضِ الْكُتُبِ الْمُصَنَّفَةِ فِي التَّوَارِيخِ وَ لَمْ أَسْمَعْهُ إِلَّا عَنْ مُحَمَّدِ بْنِ الْحُسَيْنِ بْنِ عَبَّادٍ أَنَّهُ قَالَ: مَاتَ أَبُو مُحَمَّدٍ الْحَسَنُ بْنُ عَلِيٍّ ع يَوْمَ جُمُعَةٍ مَعَ صَلَاةِ الْغَدَاةِ وَ كَانَ فِي تِلْكَ اللَّيْلَةِ قَدْ كَتَبَ بِيَدِهِ كُتُباً كَثِيرَةً إِلَى الْمَدِينَةِ وَ ذَلِكَ فِي شَهْرِ رَبِيعٍ الْأَوَّلِ لِثَمَانٍ خَلَوْنَ مِنْهُ سَنَةَ سِتِّينَ وَ مِائَتَيْنِ مِنَ الْهِجْرَةِ وَ لَمْ يَحْضُرْهُ فِي ذَلِكَ الْوَقْتِ إِلَّا صَقِيلُ الْجَارِيَةُ وَ عَقِيدٌ الْخَادِمُ وَ مَنْ عَلِمَ اللَّهُ عَزَّ وَ جَلَّ غَيْرُهُمَا قَالَ عَقِيدٌ فَدَعَا بِمَاءٍ قَدْ أُغْلِيَ بِالْمَصْطَكَى فَجِئْنَا بِهِ إِلَيْهِ فَقَالَ أَبْدَأُ بِالصَّلَاةِ هَيِّئُونِي فَجِئْنَا بِهِ وَ بَسَطْنَا فِي حَجْرِهِ الْمِنْدِيلَ فَأَخَذَ مِنْ صَقِيلَ الْمَاءَ فَغَسَلَ بِهِ وَجْهَهُ وَ ذِرَاعَيْهِ مَرَّةً مَرَّةً وَ مَسَحَ عَلَى رَأْسِهِ وَ قَدَمَيْهِ مَسْحاً وَ صَلَّى صَلَاةَ الصُّبْحِ عَلَى فِرَاشِهِ وَ أَخَذَ الْقَدَحَ لِيَشْرَبَ فَأَقْبَلَ الْقَدَحُ يَضْرِبُ ثَنَايَاهُ وَ يَدُهُ تَرْتَعِدُ فَأَخَذَتْ صَقِيلُ الْقَدَحَ مِنْ يَدِهِ وَ مَضَى مِنْ سَاعَتِهِ صَلَوَاتُ اللَّهِ عَلَيْهِ وَ دُفِنَ فِي دَارِهِ بِسُرَّ مَنْ رَأَى إِلَى جَانِبِ أَبِيهِ صَلَوَاتُ اللَّهِ عَلَيْهِ فَصَارَ إِلَى كَرَامَةِ اللَّهِ جَلَّ جَلَالُهُ وَ قَدْ كَمَلَ عُمُرُهُ تِسْعاً وَ عِشْرِينَ سَنَةً
I have seen in some books of history and Muhammad bin Hasan Ubbad has also narrated that Imam Hasan Askari 
passed away on Friday at the time of the Morning Prayer. The preceding night he wrote a number of letters to Medina. The day was 8th Rabi I, 260 A.H. At the time of his demise were present, his maid, Saqeel, his servant, Aqeed and the one whom Allah knows. Aqeed says: Imam Hasan Askari asked for water and I brought it to him. The water was heated in the Samovar.
Then we brought it. The Imam said: Prepare for the ritual prayer. We spread out a sheet in his room. The Imam took the water from Saqeel and washed his face, then washed both his hands from the elbows to the finger tips. Then he wiped his head and feet. After that he performed the ritual prayer on his bed. Then he asked for drinking water. As he was drinking the water his hand was shaking so badly that Saqeel took the bowl from him. At that moment he passed away. He was buried in Surra Man Raa in his house besides the grave of his mother. At that time was twenty-nine years of age.”
