I want to know if it is true that fasting is recommended by Sunni scholars on the day of Ashura. If so, are they following the Umayyads? Is it a celebration of the day Hussain a.s. the pious grandson of prophet and 3th Imam of Shia was killed?
What is the justification they use for recommending this fasting?
If they refer to Hadith, who are the chain of narrators of that Hadith? And is that Hadith authentic?
Also, it should be mentioned that, in Islam, fasting is a symbol of celebration and Shukr (appreciating God for his gifts)(because fasting at Eid Mabath and Eid Ghadeer is Mustahab and also Umayyads fast at their Celebration for Killing Hussain as at Ashura) . Fasting is Haraam in Eid Qurban and Fitr. But, it is Mustahab in Eid Mabath (start of prophet-hood of prophet) and also in Eid Ghadeer.
reference for fasting being symbol of celebration:
as evidence I found this Hadith from Imam Reza the 8th Imam of Shia:
سئل الامام الرضا (ع) عن صوم یوم عاشورا، قال: عن صوم ابن مرجانه تسالنی ذلک یوم صامه الادعیاء من آل زیاد لقتل الحسین (ع)
reference of Hadith: تهذیب، 4/301
Imam Reza a.s. was asked about sawm of Ashura. he said: you asked about sawm of Ibn Marjaneh (Muaviyeh). in that day Children of Ziyad took sawm for thir Eid (celebrationg) for killing Hussain s.a.
aslo Sahih Muslim in book of sawm narrated from Ibn Masud: when the sawm of Ramazan became obligatory the sawm of Ashura was left.
also shia Imams said the sawm of Ashura should be left because when sawm of Ramazan became obligatory it was left and backing to what was left by prophet is Bidat. and also Imams said who celebrate at Ashura Allah will place the Judgement day his sadness day.
only Umayyads continued sawm of Ashura and insisted on on it until it became a sunnah for sunni Muslims.
fasting is not generally symbol of celebration in Islam. but this is only for Umayyads. because they insisted fasting in this day that was left to keep their celebration day alive every year. and for this fasting and celebration at Ashura are related to each other by Umayyds. and not all Muslims or all sunni Muslims. and any one recommend fasting at Ashura has no base unless following Umayyads because Sahih Muslim says it was left by prophet when Ramazan sawm was obligatory and shia Imams said sawm at Ashura is Makruh.