One of the Five Pillars of Islam requires every Muslim who is able to do so to perform the hajj pilgrimage at least once in their lifetime. Multiple parts of the hajj require pilgrims to make tawaf, the circumambulation seven times around the Kaaba in a counter-clockwise direction. Tawaf is also performed by pilgrims during the umrah (lesser pilgrimage). However, the most interesting times are during the hajj, when millions of pilgrims gather to circle the building on the same day. In 2013, the number of pilgrims coming from outside the Kingdom of Saudi Arabia to perform hajj was officially reported as 1,379,531. In 2014, Saudi Arabia reported having completed Hajj permits for 1,389,053 international pilgrims and 63,375 for residents.
The building is called by many names in the Quran and Hadith, such as Bait (House), Bait ul Haram (Sacred House), Bait Ullah (House of Allah), Bait al-Ateeq (Ancient House), Awal ul Bait (First House) and Kaabah. The Arabic word Bait is cognate to the Hebrew Beit as used in for example Beit HaMikdash (Holy House) and Beit El/Bethel (House of God). The Arabic word Kaaba means square or cube. The Quran also mentions Bait al-Ma'mur,[Quran 52:4] the House of God in Heavens which the Kaaba symbolizes, where according to Hadith the Angels perform Tawaf and Prayers. Everyday 70000 Angels circumambulate aroung Bait al-Ma'mur. This batch will not return till the Day of Judgement.
The Kaaba is a bricked cuboid structure which is made of granite quarried from nearby Kyara Land. The Kaaba is approximately 13.1 m (43 ft) high (some claim 12.03 m (39.5 ft)), with sides measuring 11.03 m (36.2 ft) by 12.86 m (42.2 ft). Inside the Kaaba, the floor is made of marble and limestone. The interior walls, measuring 13 m (43 ft) by 9 m (30 ft), are clad with tiled, white marble halfway to the roof, with darker trimmings along the floor. The floor of the interior stands about 2.2 m (7.2 ft) above the ground area where tawaf is performed.
The wall directly adjacent to the entrance of the Kaaba has six tablets inlaid with inscriptions, and there are several more tablets along the other walls. Along the top corners of the walls runs a green cloth embroidered with gold Qur'anic verses. Caretakers anoint the marble cladding with the same scented oil used to anoint the Black Stone outside. Three pillars (some erroneously report two) stand inside the Kaaba, with a small altar or table set between one and the other two. (It has been claimed that this table is used for the placement of perfumes or other items.) Lamp-like objects (possible lanterns or crucible censers) hang from the ceiling. The ceiling itself is of a darker colour, similar in hue to the lower trimming. A golden door—the Babut Taubah (also romanized as Baabut Taubah, and meaning "Door of Repentance")—on the right wall (right of the entrance) opens to an enclosed staircase that leads to a hatch, which itself opens to the roof. Both the roof and ceiling (collectively dual-layered) are made of stainless steel-capped teak wood.
Ibn Kathir, the famous commentator on the Quran, mentions two interpretations among the Muslims on the origin of the Kaaba. One is that the shrine was a place of worship for Angels before the creation of man. Later, a temple was built on the location by Adam and Eve which was lost during the flood in Noah's time and was finally rebuilt by Abraham and Ishmael as mentioned later in the Quran. Ibn Kathir regarded this tradition as weak and preferred instead the narration by Ali ibn Abi Talib that although several other temples might have preceded the Kaabah, it was the first "House of God", dedicated solely to Him, built by His instruction and sanctified and blessed by Him as stated in Quran 22:26–29. A Hadith in Sahih al-Bukhari states that the Kaaba was the First Mosque on Earth, and the Second Mosque was the Temple in Jerusalem.
While Abraham was building the Kaaba, an angel brought to him the Black Stone which he placed in the eastern corner of the structure. Another stone was the Maqam-e-Ibrahim (literally the Station of Abraham) where Abraham stood for elevation while building the structure. The Black Stone and the Maqam-e-Ibrahim are believed by Muslims to be the only remnant of the original structure made by Abraham as naturally the remaining structure had to be demolished and rebuilt several times over history for maintenance purposes. After the construction was complete, God enjoined the descendants of Ishmael to perform an annual pilgrimage: the Hajj and the Korban, sacrifice of cattle. The vicinity of the shrine was also made a sanctuary where bloodshed and war were forbidden.[Quran 22:26–33]
According to Islamic tradition, over the millennia after Ishmael's death, his progeny and the local tribes who settled around the oasis of Zam-Zam gradually turned to polytheism and idolatry. Several idols were placed within the Kaaba representing deities of different aspects of nature and different tribes. Several heretical rituals were adopted in the Pilgrimage (Hajj) including doing naked circumambulation.
In her book, Islam: A Short History, Karen Armstrong asserts that the Kaaba was at some point dedicated to Hubal, a Nabatean deity, and contained 360 idols that probably represented the days of the year. In Guillaume's translation of Ibn Ishaq, an early biographer of Muhammad, the Ka'aba itself was addressed using a feminine grammatical form. Circumambulation was often performed naked by men and almost naked by women, and linked to ancient fertility rites. By Muhammad's day, the Kaaba was venerated as the shrine of Allah, the High God. Once a year, tribes from all around the Arabian peninsula, whether Christian or pagan, would converge on Mecca to perform the Hajj, marking the widespread conviction that Allah was the same deity worshiped by monotheists.
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