Firstly, the virtues of Muharram
Abu Hurairah may Allah be pleased with him said that: the Messenger of Allah peace be upon him said: "The best fasting after the fast of the month of Ramadhan is the fasting during the month of Muharram, and the best of prayers after the obligatory ones is the prayer observed at night". In another narration: "prayer at mid-night" (Transmitted by Muslim).
The above tradition is an evidence to the place of fasting in the month of Muharram which is next to that of Ramadhan. The virtue of fasting in this month comes with the virtue of its special periods and the great reward therein, and because fasting is one of the most beloved acts of worship to Allah.
The month of Allah "Muharram" is the first month of the Hijrah year as was reached and agreed upon during the reign of the great Caliph Umar ibn al-Khattab, and it is one of the sacred months which Allah made mentioned of in the Qur'an. Allah said:
إِنَّ عِدَّةَ الشُّهُورِ عِنْدَ اللَّهِ اثْنَا عَشَرَ شَهْراً فِي كِتَابِ اللَّهِ يَوْمَ خَلَقَ السَّمَاوَاتِ وَالْأَرْضَ مِنْهَا أَرْبَعَةٌ حُرُمٌ ذَلِكَ الدِّينُ الْقَيِّمُ فَلا تَظْلِمُوا فِيهِنَّ أَنْفُسَكُمْ
Which can be translated as:
"Verily, the number of months with Allah is twelve months (in a year), so was it ordained by Allah on the Day when He created the heavens and the earth; of them four are Sacred, (i.e. the 1st, the 7th, the 11th and the 12th months of the Islamic calendar). That is the right religion, so wrong not yourselves therein,…" (Q9:36).
Abu Bakarah may Allah be pleased with him narrated that the prophet (peace be upon him) said: "…the year is made up of twelve months among which four are sacred: three consecutive; Dhul-Qa'dah, Dhul-Hijjah and Muharram, and Rajab of Mudar which is between Jumadaa and Sha'baan" (Agreed upon)
Allah has attached this month to His name and He does not do that except to special things among His creation such as the House of Allah, the Messenger of Allah and so on, and it was named Muharram as an emphasis on its sanctity because the Arabs used to toy with it; maintaining its sanctity a year and desecrating it another. And when Allah said: ", so wrong not yourselves therein" i.e. in these sacred months because sinning in them is more serious than in any other month.
Qatada (may Allah have mercy on him) said in the interpretation of the verse: "Know that injustice in the sacred months is greater and more serious of sins than in any other, notwithstanding that injustice in any case, is a great sin, but Allah our Lord elevates and prefers whatever He pleases over others".
Allah has made these lunar months as a source of timing for mankind basically because there are visible signs that everyone knows their beginning and end. But, it is very pathetic that most Muslims have left the use of the Hijri (Lunar) Calendar and followed the use of the Christian Gregorian Calendar which is based on fairytale months and without a divine nor reasoning base. This shows the weakness of the Muslims and the copy-cat attitude towards the non-Muslims and from among its disadvantages is the adherence of the Muslims, their heritage and future generation to the Christian history and keeping them far away from their own history which is totally intertwined with their prophet, and the symbols of their religion and worship, may Allah help us!
The hadith entails that the best type of voluntary fast is the fast in the month of Muharram, this is as per the month as a whole but with regards to fasting some days in it, then fasting in some other days is more meritorious than those of Muharram such as the fasting on the day of Arafah and six days in Shawwal.
The hadith apparently refers to fasting the entire month of Muharram. Meanwhile, some scholars have said that it refers to an encouragement to fast most of it and not really to fast the whole month in view of the saying of Aisha (may Allah be pleased with her) that: "I never witnessed the Messenger of Allah fasting an entire month except for the month of Ramadhan and I have never seen him fast so much in a month as he did in Sha'ban" (Muslim).
O Allah wake us up from our slumber and give us the readiness before we depart this world.
Secondly, the day of Ashuraa in history
Aishah, peace be upon her, said that "Ashura was being fasted by the Quiraish during the era of ignorance and the prophet peace be upon him used to fast it too, and when he came to Madinah he fasted it and ordered the Muslims to fast it. And when the fast of Ramadhan was ordained, he left the fast of Ashura. So, whoever likes should fast it and who wishes not should leave it". (Bukhari and Muslim).
The tradition is an evidence that the people of the era of ignorance knew the position of the day of Ashuraa and that it was a famous day among them and used to fast in it as well as the prophet peace be upon him then. He continued fasting it before the migration but without ordering people to fast it. This tells of the sanctity of this day among the Arabs during the era of ignorance and that was why they used to cover the Ka'bah on that day as also contained in the hadith of Aishah; "they used to fast Ashura before Ramadhan fast was ordained and it was a day in which the Ka'abah was being covered…" (Bukhari).
Al-Qurtubi said: The narration of Aishah shows that it was known to them at that time, and that may be because they got it from the rites of Ibraheem and Ismail peace be upon them both – since they were their descendants – as well as many rites of Hajj and umrah that relate to the both of them .
From the generality of the evidences one can deduce that the fast of Ashura was an obligation at the beginning after the migration to Madinah, Salamah ibnal-Awka' said: The prophet peace be upon him ordered a man from Aslam to announce to the people that whoever had eaten should hold back and fast the rest of the day, and that who had not eaten should fast because today is the day of Ashura".
But, when Ramadhan fast was ordained in the second year after migration the obligatory nature of Ashura fast was cancelled and it became a desirous act of worship (sunnah) and the only time it was obligatory was during the first part of the second year of the Hijra because Ramadhan fast was ordained in the middle of the same year. Moreover, towards the last days of the prophet, he made the intention not to fast Ashura day alone, rather he would fast the day before it too to oppose the practice of the Jews.
The original Arabic text by Sheikh Salih Al-Faozan