Question: May we, in our country, observe Sawm (fast) for two days as a precaution to be sure of observing Sawm on the Day of `Arafah (9th of Thul-Hijjah)? Radio broadcasts tell us that tomorrow is the Day of `Arafah, while it coincides with the 8th of Thul-Hijjah according to our calendar.
Answer: The Day of `Arafah is the day when pilgrims stand in `Arafah (performing one of the rituals of Hajj). Observing Sawm on this day is permissible except for a person who is actually performing Hajj. Thus, if you like, you may observe Sawm on this day... read more here.