Ahl u Sunnah often wonder how Shi'a deem mourning upon the tragedic killing of Imam Hussain (as) a Prophetic Sunnah while the fact is Prophet (ﷺ) had already died when the event of Karbala happened.
The answer to this question is in their own books.
Ahmad bin Hanbal (Died 241 AH) narrates like this :
حَدَّثَنَا عَبْدُ الرَّحْمَنِ، حَدَّثَنَا حَمَّادُ بْنُ سَلَمَةَ، عَنْ عَمَّارِ بْنِ أَبِي عَمَّارٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ: " رَأَيْتُ النَّبِيَّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ، فِي الْمَنَامِ بِنِصْفِ النَّهَارِ أَشْعَثَ أَغْبَرَ مَعَهُ قَارُورَةٌ فِيهَا دَمٌ يَلْتَقِطُهُ أَوْ يَتَتَبَّعُ فِيهَا شَيْئًا قَالَ: قُلْتُ: يَا رَسُولَ اللهِ مَا هَذَا؟ قَالَ: دَمُ الْحُسَيْنِ وَأَصْحَابِهِ لَمْ أَزَلْ أَتَتَبَّعُهُ مُنْذُ الْيَوْمَ " قَالَ عَمَّارٌ: " فَحَفِظْنَا ذَلِكَ الْيَوْمَ فَوَجَدْنَاهُ قُتِلَ ذَلِكَ الْيَوْمَ
Ammar ibn Abi Ammar from Ibn Abbas: 'I saw the Prophet (ﷺ) in a dream, in the middle of the day and he was disheveled and covered with dust.' He was holding a container full of blood!' I said, 'May my parents be sacrificed for you O Apostle of Allah (ﷺ) ! What is this?!' He (ﷺ) replied, 'This is the blood of Hussain (as) and his companions. I am still collecting the blood since the start of that day.' Ammar (narrator) said: 'We memorised that day (of the dream) and we found that indeed Hussain died on the day of Ashura (i.e. 10th of Muharram).'
Investigator of this book Sh'ouaib Al-Arna'ut said : This Narration is Strong on the critera of Bukhari and Muslim.
Ahmad bin Hanbal has narrated it his another book.
Investigator of this book Wasiullah Abbas said : Chain of Narration is Authentic.
Hakim Neysaburi (Died 405 AH) also narrated it in his compilation of authentic narrations and then said :
This Narration is authentic on the criteria of two Sahih books.
Shams u Deen Dahabhi (Died 748 AH) also said same words about this narration.
Tabarani (Died 320 AH) also narrated in his book through his own chain.
Nur u Deen Al-Haythami (Died 807 AH) then said :
Ahmad and Tabarani has narrated it and all the narrators of Ahmad bin Hanbal's chain are reliable.
Khateeb Baghdadi (Died 463 AH) alsi narrated it.
Abu Bakr Behayqi (Died 458 AH) also narrates it.
Investigator of this book Sayed Ibrahim said that Chain of narration is Good.
Ibn Kathir Al-Dimishaqi (Died 774 AH) after quoting this narration said : Its chain of narration is Good.
Al-Bidayah wa Al-Nihayah - Ibn Kathir // Volume 2 // Page 53 // Edn. Bait ul Afkaar Amaan Jordan.
Khateeb Tabrizi also narrates and the Investigator Zubair Ali Za'i said it is Authentic.
Shams u Deen Qurtubi (Died 671 AH) after quoting this narration said : Its chain is Authentic and there is no criticism upon it.
Abu Bakr Ibn Abi Duniya (Died 281 AH) also narrates it
Ab'd bin Hameed (Died 249 AH) also narrated it
Investigator of the book Mustafa Al-Adwi declared it Authentic.
Pakistani Salafi Scholar Zubair Ali Za'i who was very strict in his methodology even dared to say following thing about this narration :
میرے علم کے مطابق کسی بھی معتبر محدث یا قابل اعتبار محقق نے س روایت کو منکر، شاذ اور ضعیف نہیں قرار دیا ہے۔
As far as my knowledge is concerned, not a singe reliable Muhadith nor a reliable Investigator has declared this narration to be denounced, strange or weak.
Maqalaat - Zubair Ali Za'i // Volume 2 // Page 410 // Edn. Al-Kitab International Delhi India.
CONCLUSION : This Narration is Authentic.
Now the question is what is significane of seeing Prophet Muhammad (ﷺ) in dream. Regarding this we will quote an authentic narration from Sahih Bukhari like this :
قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَنْ رَآنِي فِي الْمَنَامِ فَقَدْ رَآنِي فَإِنَّ الشَّيْطَانَ لاَ يَتَمَثَّلُ بِي " .
Messenger of Allah (ﷺ) said : One who sees me in his dream really sees me because Devil (Shaytaan) can't take my form.
Sahih Al-Bukhari - Bukhari // Page 1206 // Number 6994 // Edn. Dar u Salam Riyadh Saudi Arabia.
Abdullah bin Abbas was well know about the face of Prophet Muhammad (ﷺ) and his dream reflect the pain and agony felt by Prophet (ﷺ) when his beloved grandson was killed by people of this Ummah that too upon his name. This narration is critical in the sense that mourning upon Imam Hussain (as) is done by Prophet Muhammad (ﷺ) on the day of Ashura.
