why does jewish law prohibit the eating the flesh of the pig?
The first site gives the Jewish point of view -- Jews don't eat pork because the Torah forbids it. The second site speculates on possible ancient reasons for its prohibition.
http://www.jewishvirtuallibrary.org/jsource/Judaism/kashrut.html
http://en.wikipedia.org/wiki/Religious_restrictions_on_the_consumption_of_pork