Some people think that if they were truly spiritual, they would never eat. In truth, few acts are as divine as eating food. Eating is similar to sifting gold. You grasp the divine spark within a food and reject the dross. And then, in the mitzvahs energized by that food, you carry that divine spark back to its origin within the oneness of its Creator. That is why there are foods that are forbidden and foods that are permissible. The Hebrew word for “forbidden” is assur—meaning tied down. “Permissible” is mutar—untied. Kosher means “fit.” Foods that are assur are...