Hebrew might be a very good candidate as well. You'd get some interesting fireworks if people demanded those posters got taken down. And of course: Aramaic wou

Hebrew might be a very good candidate as well. You'd get some interesting fireworks if people demanded those posters got taken down. And of course: Aramaic would be most interesting indeed. So possibly a poster with : Hebrew, Aramaic, and Arabic, the three original languages of 3 major monotheistic religions. I think this also meets the requirement that the only words should be "In God We Trust".