I came across this notable observation yesterday when looking over some photos in Earthly Footsteps of the Man of Galilee.
The Grand Mosque of Damascus is one of the most interesting buildings in the East. It is quadrangular in form, one hundred and sixty-three yards wide, by one hundred and eight yards long. A lofty wall of fine masonry surrounds it. A few years ago the building was almost destroyed by fire.
One of the most wonderful things about this mosque is an inscription which is pointed out to the tourist. It runs over an arch in the second story. You can see even in this picture the Greek letters which form the following sentence: “Thy kingdom, O Christ, is an everlasting kingdom, and Thy dominion endureth throughout all generations.” This is the Septuagint rendering of Psalms, cxlv : 13, with the simple addition of the name of Christ. What a curious inscription to find on a Moslem mosque! And yet, how true it is that the kingdom of Christ is an everlasting kingdom. To-day the power of Mohammedanism is waning.
Photo from Earthly Footsteps of the Man of Galilee
A 2010 article in the Wall Street Journal gives the history: Muslims reused stones of the church they razed. The builder of the mosque, al-Walid, was also responsible for the construction of the Al Aqsa Mosque in Jerusalem.
Unfortunately the last observation in the quotation above has proven false. But that is in accord with Scripture which speaks of the numerous enemies present on earth when Jesus returns (Ps 2; Zech 14; Rev 19).