conservative judaism also teaches jews not to do activities in the 39 prohibited categories of work "(melacha)." conservative rabbis are often less strict about what is "melacha" than orthodox rabbis are. conservative rabbis are almost always less strict about what is a prevention "(shevut)" than orthodox rabbis. for example, conservative rabbis allow jews to use electricity on shabbat for many purposes. they do not allow jews to use electricity to do any of the 39 prohibited categories of work.