There is a very logical reason as to why three religions find the land under the Dome of the Rock very significant to their history. Each religion has a book of scripture that it believes to be the true word of God. The Koran (Islam) says that the land upon which the Dome of the Rock stands is the very place that their prophet Muhammad was taken up into heaven. However, the Jewish Torah (Old Testament) signifies that this exact place is where King Solomon's temple was, which gives them as his posterity claim to the land. The inscription on the Dome of the Rock calls out to Christianity to think of Jesus as a messenger of God, but not actually the son of God, nor to make him out to be a god himself. But that's not the only thing that tugs at Christians because they believe that King's Solomon's temple is where Christ was presented as a baby, taught as a 12 year old, and drove out the money changers as written in The New Testament. Christianity and Jewery both agree with King Solomon's temple being on that spot, so since both are so closely connected here, it may be why they are generally allies when facing the debate for Islamic claim to the site.