Vegetarianism in Noahide Law
Rabbi Yoel Schwartz (Jerusalem Court for Bnei Noah)
It is not good for a person to be a total vegetarian if he is doing so because he is trying to be merciful toward animals. There is a danger that such a person will feel that he has fulfilled his duty and will become unmerciful toward other species, including human beings. In his book Mein Kampf, Hitler, the biggest criminal of the human race, said that he used to feed rats because he felt sorry for them. Of course, doctors have proven that it is not necessary to be excessive in the consumption of meat so as to remain healthy. Human teeth were created like those of an animal that eats vegetables and fruits. Adam was prohibited from eating meat. Only during the time of Noah was this prohibition lifted. This is because Noah saved animals from the flood and was allowed after that to eat meat. The Torah not only permits, but advises man to eat meat so that he recognize the difference between man and animal. Rabbi Abraham Issac HaCohain Kook explained it in this way: “The Torah commanded us to eat meat for by doing so we realize that G-d gave us guidelines that teach us to be careful not to cause needless injury to other members of creation. If we are careful for these other members of creation, then we will be doubly sure of being careful in our daily contact with the crown of creation, which is mankind”.
The same approach is taken by Sabbatarian groups.