The virtue of fasting in the month of Muharram
Allāh, the Most Gracious, the Most Merciful;
All the praise and Thanks are due to Allāh, the Lord of the al-ā’lamīn. I testify that there is none worthy of worship except Allāh, and that Muhammad, sallallāhu alayhi wa sallam, is His Messenger.
Fasting in the month of Muharram is highly desired, especially on the tenth day (‘Āshurā) due to its great virtue. The Messenger of Allah (sallallāhu 'alaihi wa sallam) has been reported as saying when asked which solāt is better after obligatory solāt: “Solāt in the middle of the night." He was asked again which fast is better after Ramadhān. He said: “in the month that is called al-Muharram.” [Ahmad, Muslim, and Abu Dawud]
This hadith clearly indicates the importance of voluntary fasting in Muharram, among all the months. The prophet (sallallāhu 'alaihi wa sallam) however, emphasizes the fast of the tenth day, ‘Āshūrā.
Fasting on ‘Āshūrā’ was a gradual step in the process of introducing fasting as a prescribed obligation in Islām. Fasting appeared in three forms. When the Messenger of Allāh (Sallallāhu 'alaihi wa sallam) migrated to Madīnah, he told the Muslims to fast on three days of every month and on the day of ‘Āshūrā’, then Allāh made fasting obligatory when verse was revealed: “… observing the fasting is prescribed for you…” [Al-Baqarah 2:183] The obligation was transferred from fasting of ‘Āshūrā’ to the fast of Ramadhān, and in the field of Usūl al-Fiqh that it is possible to abrogate a lighter duty in favour of a heavier duty.
Before the obligation of fasting ‘Āshūrā’ was abrogated, fasting on this day was obligatory, as can be seen from the clear command to observe this fast. Then it was further confirmed later on, then reaffirmed by making it a general command addressed to everybody, and once again by instructing mothers not to breastfeed their infants during this fast. It was reported from Ibn Mas’ūd that when fasting Ramadhān was made obligatory, the obligation to fast ‘Āshūrā’ was lifted, i.e., it was no longer obligatory to fast but it is still desirable (mustahabb).
The word "‘āshūra" is derived from ashara, which means ten. The observation of this day goes back to Prophet Mūsa bin ‘Imran (‘alaihis-salam). In a hadīth related by Ibn Abbās (radiallāhu`anhu) “When the Messenger of Allāh (sallallāhu 'alaihi wa sallam) arrived in Madinah, he found the Jews fasting the day of ‘Āshurā. He inquired why they did so. They replied that it was a good day, the day which Allāh delivered Prophet Mūsa (‘alaihis-salam) and the children of Israel from their enemy. As gratitude Mūsa (‘alaihis-salam) fasted that day. The Prophet (sallallāhu 'alaihi wa sallam) responded: “I have more right to Mūsa than you.’ He fasted the day and commanded the believers to fast.” [Al-Bukhāri and Muslim (2520)]
This hadith indicates that the Prophet (sallallāhu 'alaihi wa sallam) was in complete agreement with Prophet Mūsa (‘alaihis-salam) as well as the other prophets. The point here is that the Messenger of Allah (sallallāhu 'alaihi wa sallam) would always do an act of worship if it was prophecy reported from any of the prophets. Earlier, we see how he told us that the best voluntary fast is the fast of Dawud.
This is why the following hadith is of great interest to us. Ibn Abbās (radiallāhu`anhu) related when Prophet Muhammad (sallallāhu 'alaihi wa sallam) observed the day of ‘Āshurā and commanded his followers to observe it, they asked him: "O Messenger of Allāh (sallallāhu 'alaihi wa sallam) this is the day the Jews, and Christians respect and honor.” Thereupon the Prophet (sallallāhu 'alaihi wa sallam) promised them: “By next year, Allāh willing, we shall fast the ninth, (along with the tenth which he was accustomed).” The next Muharram, the Prophet (sallallāhu 'alaihi wa sallam had passed away. [Muslim (2528)]
It is because the believers, desire to emulate Prophet Mūsa (‘alaihis-salam) in fasting on ‘Āshurā do so with the desire not to participate in the festivity of the People of the Book, who have reduced the day to a mere formality. The Prophet (sallallāhu 'alaihi wa sallam) decided to remove this ambiguity with the fast of the ninth day.
Our ulama' analyzing all reports from the Prophet (sallallāhu 'alaihi wa sallam) regarding Muharram stated the fast of Muharram can be done in three ways:
1. Fasting three days of Muharram, the ninth, tenth and eleventh.
2. Fasting on the ninth and tenth day because of two previous hadiths.
3. Fasting on the tenth day alone.
Of much interest to us Muslims these days should be the fasting of the 9th and the 10th of Muharram. The Prophet (sallallāhu 'alaihi wa sallam) said about the voluntary fasting on the Day of ‘Āshurā: “It expiates the sins of the preceding year.” [Muslim; Fathul Bāri, Vol V, p.152: reported by Qatāda]
Muslim commented in his Sahih:"The Day of ‘Āshurā was the day when Mūsa (‘alaihis-salam) and his men got freedom from the hands of the pharaoh and it was in the sacred memory of this great event that the Muslims observed voluntary fasting. The idea underlying this is to stress the affinity amongst the messengers of Allāh and to show that religious devotion is a constant flow from one generation to another. The Prophet (sallallāhu 'alaihi wa sallam) came not to abrogate all the earlier religious practices but to codify and preserve them for all times to come in ideal forms."
[Via Islamic Finder]