Youm e Aashura is commemorated for the great sacrifice of Hazrat Imam Hussain (R.A) and his family. All masalik (groups) of Muslims including the Shia community remember this day when Hazrat Imam Hussain (R.A) refused to bow before a cruel dictator and sacrificed his and his family's lives in the way of Haq in Karbala. Keeping aside the debate about how Shias have transgressed in the matter of beliefs and rituals we come to our point that there is another importance of Youm e Aashura especially for Sunnis. Here it is actually not only linked with Aashura and Karbala events, A great number of Sunni Muslims fast on this day of Ashura based on narrations attributed to our Holy Prophet Hazrat Muhammad (Peace be upon him).
Har Musalman kay liyay Youm e Aashur ki ahmiat janana boht zaroori hai. Yaum e Aashur ki ahmiat Waqaya Karbala ki waja say bhi hai aur Jab Hazrat Musa (A.S) ko Allah Talah nay Firaun say bachaya tha us waja say bhi hai.
The fasting is to commemorate the day when Moses (Musa) (Peace be upon him) and his followers were saved by Allah from Pharaoh by creating a dry passage in the Red Sea. According to the Ahadith, the Jews used to fast on the tenth day. So Hazrat Muhammad (Peace be upon him) recommended to be different from the Jews and also recommended fasting for Muslims but for two days instead of one. The days of fasting for Muslims are 9th and 10th or the 10th and 11th day of Muharram. This fasting is optional and not compulsory for Muslims. This is a nafal fasting which enhances the ranks of believers in the eyes of Allah if done with the sincerity of heart and purity.
Hazrat Muhammad (Peace be upon him) used to fast on the day of Ashura, 10th Muharram, in Makkah. When fasting during the month of Ramadan became obligatory, the fast of Ashura was made optional. This is narrated by Hazrat Ayesha (R. A), in Sahih Muslim, (Hadith-2499).
During Hijrah when Hazrat Muhammad (Peace be upon him) led the believers to Madina, he found the Jews of that area observing fasts on the day of Ashura same as Muslims. At this point, Hazrat Muhammad (Peace be upon him) directed Muslims to fast in the combination of two or three consecutive days including the 10th of Muharram (e.g. 9th and 10th or 10th and 11th).