Dhu al-Hijjah

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:

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:

One of the wives of Muhammad said: "Allah's Messenger used to fast the [first] nine days of Dhul-Hijjah, the day of 'Ashurah, and three days of each month." (Reported by Abu Dawud)

In Islamic eschatology about Hajj and Mahdi:

In Dhu al-Qi'dah (Islamic month), there will be fight among the tribes, Muslim pilgrims will be looted and there will be a battle in Mina in which many people will be slain and blood will flow until it runs over the Jamaratul Aqba (one of the three stone pillars at Mina). The man they seek will flee and will be found between the Rukn (a corner of the Kaaba containing the Black Stone) and the Maqam of Prophet Abraham (near Ka'ba). He will be forced to accept people's Bay'ah (being chosen as a Leader/Caliph). The number of those offering Bay'ah will be the same as the number of the people of Badr (Muslim fighters who participated in the Battle of Badr at time of Prophet Muhammad). Then, the dweller of Heaven and the dweller of the Earth will be pleased with him.

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