Several researches say that the Umayyad caliph, Abdel Malek Ben Marwan, decided to build the dome out of a need for a religious focal point outside of Mecca. During the period of his reign, Mecca was ruled by his rival, Abd Allah Ibn al-Zubayr, who had revolted against the Umayyads and conquered that holy city. Other researchers say Abel Malek needed a structure to compete with the palatial churches the Christians had built in Jerusalem, in order to reinforce Muslim rule in the city.This discussion is well outside my own expertise. I have no opinion about it. But I thought you would find it interesting.
A recent article by Dr. Milka Levy-Rubin in the Cathedra journal published by Yad Ben-Zvi, says the Dome of the Rock was built in order to restore Jerusalem’s place on the regional map of holy sites, not vis a vis Mecca, but rather as a rival to Constantinople, the Byzantine capital. This is why the Muslims depended on the Jewish traditions at the site.
By the way, there is an odd misstatement just before this quote. The Dome was not "erected 691 years ago." It was erected (or completed) around the year 691 C.E. This was something over 1,300 years ago, as stated correctly in the headline and the first paragraph.
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