Sunnah : Fast for the day of ‘Arafa.
Tomorrow should be the blessed day of ‘Arafa according to most places. It is sunnah to fast for those not on Hajj, as we can see by the hadith above.
It is on this day that the people who are on Hajj go to the Mountain of ‘Arafa, which is the central point in the journey, as the Prophet (Sallallahu Alaihi Wasallam) said: “Hajj is Arafa” (Ahmed, Abu Dawud, Tirmidhi) In this place, Allah boasts to His Angels about the people of ‘Arafah, and He says, “Look at My slaves who have come unkempt and dusty.”
As most of us are not away on Hajj, we should take advantage of this blessed day by fasting, repenting to Allah and supplicating. The Prophet (Sallallahu Alaihi Wasallam) reminded us:
“The best dua is dua on the day of Arafa.” [Malik’s Muwatta]