Dhu'l-Hijja

Dhu'l-Hijjah or alternatively Zulhijja (Arabic: ذو الحجة‎‎; properly transliterated, also called Zil-Hajj) is the twelfth and final month in the Islamic calendar. It is a very sacred month in the Islamic calendar, one in which the Hajj (pilgrimage) takes place as well as the Festival of the Sacrifice.

"Dhu al-Hijjah" literally means "Possessor of the Pilgrimage" or "The Month of the Pilgrimage". During this month Muslim pilgrims from all around the world congregate at Mecca to visit the Kaaba. The Hajj is performed on the eighth, ninth and the tenth of this month. Day of Arafah takes place on the ninth of the month. Eid al-Adha, the "Festival of the Sacrifice", begins on the tenth day and ends on sunset of the 13th.

According to Islamic traditions, the first 10 days of Dhu al-Hijjah are the most blessed days in which to do good deeds:

حدثنا هناد حدثنا أبو معاوية عن الأعمش عن مسلم هو البطين وهو ابن أبي عمران عن سعيد بن جبير عن ابن عباس قال قال رسول الله صلى الله عليه وسلم ما من أيام العمل الصالح فيهن أحب إلى الله من هذه الأيام العشر فقالوا يا رسول الله ولا الجهاد في سبيل الله فقال رسول الله صلى الله عليه وسلم ولا الجهاد في سبيل الله إلا رجل خرج بنفسه وماله فلم يرجع من ذلك بشيء وفي الباب عن ابن عمر وأبي هريرة وعبد الله بن عمرو وجابر قال أبو عيسى حديث ابن عباس حديث حسن صحيح غريب

Narrated Ibn Abbas: The Prophet (peace and blessings of Allah be upon him) said, "No good deeds done on other days are superior to those done on these (first ten days of Dhu al-Hijja)." Then some companions of the Prophet said, "Not even Jihad?" He replied, "Not even Jihad, except that of a man who does it by putting himself and his property in danger (for Allah's sake) and does not return with any of those things." (Reported by Tirmidhi)

Muhammad (peace and blessings of Allah be upon him) used to fast the first nine days of this month, owing to their perceived virtue:

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