Leviticus 11:2
Of the laws relative to clean and unclean beasts, which are recorded in this chapter and Deut. ch. 14 the following may be found a useful abstract. 1. In regard to quadrupeds, all beasts that have their feet completely cloven, above as well as below, and at the same time chew the cud, are clean. Those which have neither, or indeed want one of these distinguishing marks, are unclean. This is a systematic division of quadrupeds so excellent, as never yet, after all the improvements in natural history, to have become obsolete, but, on the contrary, to be still considered as useful by the greatest masters of the science. 2. With regard to fishes, Moses has in like manner, made a very simple systematic distinction. All that have scales and fins are clean; all others unclean. 3. Of birds, he merely specifies certain sorts as forbidden, thereby permitting all others to be eaten. 4. Insects, serpents, worms, etc., are prohibited; but with regard, however to those winged insects, which besides four walking legs, also have two longer springing legs, (Pedes saltatorii,) Moses makes an exception, and under the denomination of locusts, declares them clean in all four stages of their existence. In Palestine, Arabia, and the adjoining countries, locusts are one of the most common articles of food, and people would be very ill of if they durst not eat them: For, when a swarm of them desolates the fields, they prove in some measure themselves an antidote to the famine which they occasion. They are not only eaten fresh, immediately on their appearance, but the people collect them, and know a method of preserving them for a long time for food, after they have dried them in an oven. --Niebuhr's Description of Arabia, pp. 170-175.
