welcome to the forums
Catholics "have to do with" Jerusalem because it is a holy city to them wherein key events of Christ's life, passion, death and resurrection occured.
The Jerusalem Bible is a Catholic translation undertaken by a group of scholars working in Jerusalem using ancient sources. Look at the scripture forum for more information on various Catholic translations of the bible.
The Arabs who live in and around Jerusalem have nothing to do with either, except that some of them are actually Christian.
you will get more out of your time here if you take some time to play with the search function, read the rules (in the stickies above each forum) especially those on where to post your question.