The day of Ashura in Islam

The specific mention of these months does not deny or reject the sanctity of the remaining months, days and nights. The month of Ramadan is undeniably sacred and a sanctified month in the Islamic year. The day of Arafah has its own honour and nobility. Lailat ul Qadar (the Night of Decree or Power) admittedly has its special merits and virtues. But these four months were particularly labeled as sanctified just for one reason that their sanctity and holiness was confirmed even by the polytheists of Makkah in the preIslamic period.
It is Allah’s Month
The Prophet (peace and blessings be upon him) called this month ‘the month of Allah’. In fact, referring and attributing it to Almighty Allah indicates its honour and merits.
The sanctity of this month and attributing it to Allah implies that it has been declared as sacred by the Will of Allah Himself and that no one could make any changes in its sanctity and sacredness or replace it with another month as the pagans of preIslamic days of ignorance were accustomed to do.
The Prophet Muhammad (peace and blessings be upon him) said, “Allah’s month is Al Muharram.” (Narrated by Muslim)
The attribution of Muharram to Allah is to express its nobility, virtuousness and significance.
Fasting during this month
One of the merits of this month is fasting during it. This is based on the following narration of the beloved Prophet Muhammad (peace and blessings be upon him), “The most virtuous fasting after the month of Ramadan is Allah’s month Al Muharram.” (Narrated by Muslim)
This hadith clearly declares that this month after Ramadan is the best month for observing the voluntary fast, because it is Allah’s month.
The Quraish used to observe fasting on the day of Ashura in the period of pre Islamic ignorance and Allah’s Messenger (peace and blessings be upon him) also used to observe fasting on that day. When he migrated to Al Madinah, he observed fasting on that day and ordered others to do likewise. Later when the fasting of the month of Ramadan was prescribed, he gave up fasting on the day of Ashura and it became optional for one to observe or not to observe fasting.
The History of Ashura
Pharaoh ruled the entire nation of Israel and enslaved and subjugated it, afflicted it with the worst torment, slaughtering its newborn sons and keeping its females alive.
The reason why this tyrant king committed these criminal acts was the fear of the truth emerging from the offspring of this nation. They used to know, according to the glad tidings that came to them from the Prophet Ibrahim (peace be upon him). Ibrahim (peace be upon him) informed them that someone from his lineage would destroy this tyrant king and his kingdom.
This news became well known among them and pharaoh was also informed of it. The tyrant king commanded his hosts to slaughter every newborn male child of the nation in order to protect himself from due destruction.
In spite of such precautions being taken, they did not change what Allah desired. Musa (peace be upon him) was raised in this tyrant king’s home and Almighty Allah chose that the prophet Musa (peace be upon him) be born safely under the guardianship and protection of Almighty Allah until he became mature.
Musa (peace be upon him) was chosen as a prophet by Allah and sent to this brutal king. Allah blessed him with many miracles as signs of prophet-hood but the pharaoh behaved arrogantly and stubbornly. He claimed that these signs were no more than magic. He rejected this doctrine and decided to employ various types of tactics, such as fear, force and retaliation, to overcome Musa (peace be upon him) and his followers.
Pharaoh gathered his hosts, which were huge in numbers and well equipped. They pursued Musa (peace be upon him) and his followers, hoping to destroy them completely. Musa (peace be upon him) and his followers ended up at the sea with the brutal king and his hosts behind them. Musa (peace be upon him) struck the sea with his staff and it opened up for them to cross.
Musa (peace be upon him) and all those who believed and were with him walked across open paths in the sea. And Almighty Allah drowned the brutal king and his army in the sea and destroyed them completely.
Source: Islam.ru