Question: With regard to the dietary teachings in Judaism. Surely, as the bible is a spiritual book there is also a spiritual interpretation to some of the commands?
Answer: The Torah does not give any explicit reason, spiritual or otherwise, for keeping kosher. In general, we keep kosher for one or both of the following two reasons:
- We think that the Torah comes from God, and God commands kashrut in the Torah,
- There are lessons inherent in keeping kosher which transmit important Jewish values.
The most important lesson I derive from kashrut is a sensitivity towards the life of animals, and an acknowledgment that all life was created by and belongs to God. One who keeps kosher, which demands an ongoing vigilence against and awareness of what goes into one's mouth, should experience a heightened sensitivity towards the ethics of food productions and consumption, and a heightened appreciation for the concept of life.
The Torah explains that we should not eat blood because the life is contained in the blood. While Jewish tradition permits us to eat animals, we may not eat the part of the animal, that is the blood, that represents the life of the animal. That, during the shekhita, or kosher slaughter, process, is spilled on the ground and covered with dust, symbolic of giving the animal's life back to God.
Jewish tradition also holds that we are forbidden to cause undue pain to animals, called tza'ar ba'alei hayyim. The process of shekhita, using a very sharp knife, is considered one of the least painful ways to kill an animal.
When the Torah prohibits eating dairy and meat together, the only explanation given is that one should not do so in order to be holy. Here too, one might see a sensitivity towards the animal's life urging us not to mix the dead flesh of the animal with the life-giving fluid of milk.
We can only speculate on the significance of the signs of kosher and non-kosher animals (land-dwellers need to have a split hoof and chew their cud, water-dwellers need to have fins and scales). Perhaps, since they exclude animals of prey (like bears and lions) and scavengers (like lobsters and shrimp), we do not want to eat animals which live by violence or eat garbage, because we want to avoid developing those characteristics in ourselves. Animals, such as cows, which have the characteristics of chewing their cuds and split hoofs tend to be very gentle animals.
Finally, I suspect that one of the original reasons for keeping kosher was to keep the Jews distinct from the non-Jewish peoples around her. This is still one of the results of keeping kosher, though this is not the primary reason most give for doing the mitzvah in the first place.