JERUSALEM – An ancient limestone tablet covered with a mysterious Hebrew text that features the archangel Gabriel is at the center of a new exhibit in Jerusalem, even as scholars continue to argue about what it means. The so-called Gabriel Stone, a meter (three-foot)-tall tablet said to have been found 13 years ago on the banks of the Dead Sea, features 87 lines of an unknown prophetic text dated as early as the first century BC, at the time of the Second Jewish Temple.