Arafat was named so because Archangel Jibr'il عليه السلام said to Ibrahim عليه السلام at that place: 'Admit your sin and learn your rites.' Hence, it was called Arafat. Al-Mash'ar (Muzdalifah) was named Muzdalifah because Archangel Jibril عليه السلام said to Ibrahim عليه السلام at Arafat: 'O Ibrahim, move closer (izdalif) to the Sacred Monument.' Therefore, it was named Muzdalifah. Muzdalifah was also called Jam’ because the Maghrib and Isha prayers are combined there with one Adhan and two Iqamahs."
Commentary #8