According to Islamic tradition, the hill is the place where Muhammad stood and delivered the Farewell Sermon to the Muslims who had accompanied him for the Hajj towards the end of his life.

[9] On 9 Dhu al-Hijjah before noon, pilgrims arrive at Arafat, a barren plain some 20 kilometres (12 mi) east of Mecca,[6] where they stand in contemplative vigil: they offer supplications, repent and atone for their past sins, seek mercy of God, and listen to Islamic scholars giving sermons from near Mount Arafat.

[15] Fasting on the Day of Arafah for non-pilgrims is a highly recommended Sunnah which entails a great reward; Allah forgives the sins of two years.

It was narrated from Abu Qatadah that Muhammad was asked about fasting on the day of 'Arafah and he replied: It expiates for the past and coming years.Imam An-Nawawi mentioned in his book al-Majmu', "With regard to the ruling on this matter, Imam As-Shafi'i and his companions said: It is mustahabb (recommended) to fast on the day of Arafah[16] for the one who is not in Arafah.

As for the pilgrim who is present in Arafah, Imam As-Shafi'i in his book Al-Mukhtasar and his followers declared 'It is mustahabb (recommended) for him not to fast'."