Power Point of a speech on First Amendment law governing the eruv (an enclosure which, under Jewish law, allows people to carry otherwise prohibited items on the Jewish Sabbath). In particular, I conclude that (1) the Establishment Clause allows municipalities to authorize an eruv; and 2) the Free Exercise Clause does not require municipalities to do so, as long as their refusal is on grounds neutrally enforced against all citizens (such as a ordinance prohibiting all signs on utility poles).