(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.”
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.
To read more Day of Arafaah
The Day of Arafaah is Dhu'l-hijjah 9.
What are the Virtues of the Day of Arafaah ?
To know the answer is in Islam Q&A
Allah (the Exalted and Almighty) has said
O, you who believe! send your salat on (ask Allah to bless) Him Muhammad Sallalahu Alayhi wa salam and you (should greet) salute him with the Islamic Way of greeting (salutation ie. As salamu Alaikum)
(Quran Al Ahzab: 56)
Let's fasting on the Day of Arafaah.
May Allaah bless our Prophet Muhammad and his family
and companions, and those who follow them in truth.
May Allah accept all our good deeds.