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There is consensus among Muslim scholars that spending the Day at `Arafah is the most important part of Hajj. The Prophet (peace and blessings be upon him) ordered an announcer to proclaim "Hajj is (spending the day at) `Arafah, so he who joins other pilgrims on the night of Muzdalifah before dawn will be considered as having performed Hajj."

In this regard, we will cite what Sheikh Sayyed Sabiq states in his well-known book Fiqh Us-Sunnah:

Staying at `Arafah means physical and mental presence in any part of `Arafah, whether one is awake, asleep, riding, sitting, lying down, walking, and regardless of whether one is in a state of purity or not, for example a menstruating woman, or one giving birth, or a person having a wet dream.

There is consensus among Muslim scholars that spending the Day at `Arafah is the most important part of Hajj. Ahmad and the compilers of the Sunan have reported from `Abdur Rahman ibn Ya`mur that the Prophet (peace and blessings be upon him) ordered an announcer to proclaim "Hajj is (spending the day at) `Arafah, so he who joins other pilgrims on the night of Muzdalifah before dawn will be considered as having performed Hajj."

Most Muslim scholars are of the opinion that the time to spend in `Arafah begins from noon of Dhul-Hijjah 9 until dawn of Dhul-Hijjah 10 and that any part of this period of time, day or night, may be spent in `Arafah (to fulfill this condition). A pilgrim choosing to spend the day time at `Arafah must stay there until after the sunset. But if someone spends the night at `Arafah he is not obligated to stay for any specific length of time. Ash-Shafi`i holds that extending the stay at `Arafah until nightfall is a Sunnah.