Jewish law states that "six days you shall work, on on the seventh day you shall rest". The Talmud explains that this "rest" (while including) does not specific

Jewish law states that "six days you shall work, on on the seventh day you shall rest". The Talmud explains that this "rest" (while including) does not specifically refer to manual labor, rather the act of creation, embodied in the 39 "categories" of work which were performed in, and when building, the Tabernacle (the predecessor to the Temple, originally built after Sinai, which accompanied the Jews throughout their travels in the desert). The Talmud discusses at length what is included in these categories, what is considered similar enough to be forbidden as well, etc. Essentially, these aren't loopholes, but ways of getting the same results without performing any forbidden acts. Of course, there are things which are frowned upon as not within the "spirit" of the Sabbath, e.g. leaving a television on. In addition, I noticed some people mentioned the "eruv", a string around a neighborhood which allows the residents to carry within it on the Sabbath. This too is not really a loophole, as the biblical prohibition of carrying on the Sabbath was only to and from or inside a public thoroughfare (at least 24-36 feet wide, with at least 600,000 people passing through each day), which is relatively uncommon. The Rabbis of the Talmud (in accordance with the teaching "make boundaries around the Torah"in order to prevent people from accidentally transgressing the Torah) further added the prohibition to carry to and from or inside "semi-public" areas or, to put it another way, non-private areas, or from one area (private or otherwise) to another. With this added prohibition, however, they included an exception. That is, if one puts a fence or string around the entire area (again, this excludes "true" public thoroughfares), thereby symbolically making it one area, one is permitted to carry within it. This is not technically a "loophole", but a solution that ensures that one remembers not to carry in a public area on the Sabbath. Jewish law is much more complex, logically built, and developed than one might think, and I encourage you not to dismiss most observant Jews' practice of it as "cheating", or "hypocritical". This is of course a very limited discussion of the topics involved, as most observant Jews spend years (!) studying the laws and their implications. For further reference I would recommend you visit http://www.chabad.org/search/keyword_cdo/kid/6967/ http://www.chabad.org/search/keyword_cdo/kid/6967/.