To be sure as Orthodox Jews we believe that God gave the Torah to be relevant for all times (yemot hamoshiach and the kashrut of bacon aside). Often it is argued that it can not be the case that something in nature has changed which would render something in the torah to no longer be true or observable. For instance, it is often pointed out in kiruv circles that the torah states that a pig is the only animal which has cloven hooves but does not chew its cud and since the Torah is true not only has another animal never been found with such criteria but one never will. From what I am told this is utilized as one of the many proofs of the Torah’s divine truth by many orthodox outreach organizations.
Another example: It is widely claimed in many segments of the Orthodox community that homosexuality must result from nurture and not nature. This is so, it is claimed, because God gave the torah for all times, so it must be the case that everyone can in theory marry someone of the opposite gender. Indeed the torah commands “Therefore shall a man leave his father and mother and cleave to his wife.” Since the Torah forbids homosexual acts and commands heterosexual marriage it must be the case that all Jews are able to be or at least act heterosexual with the right help.
Why is it then that kashrut organizations can forbid certain vegetables, telling us there is no way to check them for bugs and we do not bat an eye? Does not the torah tell us in Birashit that all the “growing things are for you to eat?” If the torah is applicable for all times and there is no way to check brussel sprouts for bugs why doesn’t this bother us theologically as much as claims for the genetic etiology of homosexuality? Is it perhaps that a culture has developed among us whereby when it comes to forbidding something we have no problem expanding the torah, but when it comes to finding ways to include and permit we do? Perhaps the case, as Rabbi J. Telushkin has said, “Though Hillel wins in the Talmud, it is Shami who wins in Jewish life today.”