It is Sunnah to fast the first nine days of Dhul-Hijjah, especially the day of `Arafah, for those who are not performing Hajj. This is confirmed by the following hadiths:
1. Abu Qatadah (may Allah be pleased with him) is reported to have said that the Prophet (peace and blessings be upon him) said: "Fasting on the day of `Arafah is an expiation for two years, the year preceding it and the year following it. Fasting the day of `Ashurah is an expiation for the year preceding it." (Reported by "the group," except for Al-Bukhari and At-Tirmidhi)
2. One of the wives of the Prophet (peace and blessings be upon him) said: “Allah’s Messenger used to fast the [first] nine days of Dhul-Hijjah, the day of `Ashurah, and three days of each month." (Reported by Abu Dawud).
3. `Uqbah ibn `Aamr (may Allah be pleased with him) is reported to have said that the Messenger of Allah (peace and blessings be upon him) said: "The day of `Arafah [for those performing Hajj], the day of sacrifice, and the days of Tashreeq are `Eids (feasts) for us – the people of Islam – and they are days of eating and drinking."
4- Abu Hurayrah (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) forbade fasting on the day of `Arafah for one who is actually at `Arafah." (Reported by Ahmad, Abu Dawud, An-Nasa'i, and Ibn Majah).
Q: As the ten blessed days of Dhul-Hijjah are approaching, I know that these are virtuous days, in which good deeds are highly recommended by the Prophet (peace and blessing be upon him). But my question is: could you please shed light on the virtue and merits of these blessed days?
You should know, dear brother in Islam, that the virtue of these ten days is based on many things:
1. Allah swears an oath by them, and swearing an oath by something is indicative of its importance and great benefit. Almighty Allah says, (By the dawn; by the ten nights) (Al-Fajr 89: 1-2). Ibn `Abbas, ibn az-Zubayr, Mujahid and others of the earlier and later generations are of the opinion that this refers to the first ten days of Dhul-Hijjah. Ibn Kathir said: "This is the correct opinion." (Tafsir Ibn Kathir, 8/413)
2. The Prophet (peace and blessings be upon him) testified that these are the best days of this world, as we have already quoted above from authentic hadiths.
3. The Prophet (peace and blessings be upon him) encouraged people to do righteous deeds because of the virtue of this season for people throughout the world, and also because of the virtue of the place, for the pilgrims to the Sacred House of Allah.
4. The Prophet (peace and blessings be upon him) commanded us to recite during this time a lot of tasbih (glorification of Allah), as well as tahmid (praising Allah) and takbir (saying 'Allah is Greatest'). `Abdullah ibn `Umar (may Allah be pleased with him and his father) reported that the Prophet (peace and blessings be upon him) said: "There are no days greater in the sight of Allah and in which righteous deeds are more beloved to Him than these ten days, so during this time recite a great deal of tahlil (saying: 'there is no god but Allah'), takbir and tahmid." (Ahmad)
5. These ten days include the Day of `Arafah, on which Allah perfected His religion. Fasting on this day will expiate for the sins of two years. These days also include the Day of Sacrifice, the greatest day of the entire year and the greatest day of Hajj, which combines acts of worship in a way unlike any other day.
6. These ten days include the days of Hajj.
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