The 9th day of the last Islamic Lunar Calendar Month of Dhul Ḥijjah, and the day before Eid al-Adha This is one of the most important days of the year for Muslims, and there are special prayers and supplications recommended for this day – such as praying for forgiveness and reciting Dua al-Arafah which was composed by Imām Ḥusayn (‘a).