We are entering the blessed days of Dhul Hijjah. As we all know these are most blessed days of the year.
It was narrated from Ibn ‘Abbaas (may Allaah be pleased with him) that the Prophet (peace and blessings of Allaah be upon him) said: “There are no days on which righteous deeds are more beloved to Allaah than these ten days.” They said: “Not even jihad for the sake of Allaah?” He said: “Not even jihad for the sake of Allaah, unless a man goes out himself for jihad taking his wealth with him and does not come back with anything.”(Bukhari)
And among the greatest of deeds we can participate in, besides hajj, are fasting, reciting dhikr and offering the udhiya on ‘Eid.

. ” It was reported from Abu Qutaadah (may Allaah be pleased with him) that the Messenger of Allaah (peace and blessings of Allaah be upon him) was asked about fasting on the Day of ‘Arafaah. He said, “It expiates for the sins of the previous year and of the coming year.” Narrated by Muslim.

This (fasting) is mustahabb for those who are not on Hajj. In the case of the one who is on Hajj, it is not Sunnah for him to fast on the Day of ‘Arafaah, because the Prophet (peace and blessings of Allaah be upon him) did not fast on this day in ‘Arafaah. It was narrated that he forbade fasting on the Day of ‘Arafaah in ‘Arafaah.”