Most Christians think that because Jesus came we no longer need to follow the rules of Kosher or any of the others but lets talk about this one now. Paul decided not to do these thing 70 years after Jesus and he never met the man . He (Jesus) told his followers to never stop following the Torah. Jesus kept Kosher, celebrated Passover, and kept Shabbat. Which is how we get Messianic Jews. They believe in Jesus and follow his teaching of the Torah. I think they should be called Torah observant Christians. Because if you believe in Jesus you are not a Jew.
from the website http://www.whatjewsbelieve.org/explanation9.html
IN SHORT... Many people -- some but not all Christians, and some Jews as well -- erroneously believe that just as one can be Black and Christian, just as one can be Asian and Christian, one can also be Jewish and Christian. This is not true. The Jews are not a race. There is no genetic code passed from either mother or father to the child that makes that child a Jew. Genetics might indicate that ones ancestors were Jews, but that does not, in fact, make one a Jew. Even if all, or some, of the genetic code in a child proved to be of Jewish origin, that would not make the child a Jew. Jewish law determines who is a Jew, and Jewish law is quite clear. If a person's mother is a Jew, and that person has not converted to another faith and wishes to identify solely as a Jew, then that person is considered fully Jewish. In addition, a convert to Judaism is fully Jewish. Although one cannot convert to become a member of a race (for example one cannot convert to become an Asian or an African-American), one can convert to become a Jew. If someone who is Asian or African-American converts to Judaism, that person obviously remains an Asian or an African-American, and at the same time is a Jew. However, if one converts from Judaism to another faith, one is no longer a Jew.
But for those of us who do not see Jesus as an important person we really don't care if Paul says it is fine to do something. G-d can see all futures and if he knew at another time in life we would be able to make the kosher laws not valid he would have said so. He knew the world was round and it is said "He who sits above the circle of earth." This was write hundreds of years before anyone found out the earth was round. So he knew how things would change. Maybe at that time it was due to not having clean ways to eat pigs or shrimp. But for us it is about the fact that he said so. He said not to do it. If someone came to America today and said it is fine to eat Monkeys and they were starting a farm to raise monkeys to be eaten would that mean we will all start eating monkeys. No I think people would still feel that eating Monkeys wasn't right and some would not do it. But the next few generations would grow up with Monkey restaurants and they would start to eat monkeys with no problems. Well that is how it is to be a Jew. One person said it was ok to eat these things and even if it is out dated and made clean now it doesn't matter because we know we are not suppose to eat it for no other reason than because we were told not to. It is just like being a parent. You don't have to tell you kids why they can't do something that they think is fine to do. You know what it is best for them even if they think you are wrong. G-d is our father and he knows what is best without us undermining him with why. So no it is not out dated. This falls under the rules of "because I said so and I am the parent."