11:1-47 What animals were clean and unclean. - These laws seem to have been intended, 1. As a test of the people's obedience, as Adam was forbidden to eat of the tree of knowledge; and to teach them self-denial, and the government of their appetites. 2. To keep the Israelites distinct from other nations. Many also of these forbidden animals were objects of superstition and idolatry to the heathen. 3. The people were taught to make distinctions between the holy and unholy in their companions and intimate connexions. 4. The law forbad, not only the eating of the unclean beasts, but the touching of them. Those who would be kept from any sin, must be careful to avoid all temptations to it, or coming near it. The exceptions are very minute, and all were designed to call forth constant care and exactness in their obedience; and to teach us to obey. Whilst we enjoy our Christian liberty, and are free from such burdensome observances, we must be careful not to abuse our liberty. For the Lord hath redeemed and called his people, that they may be holy, even as he is holy. We must come out, and be separate from the world; we must leave the company of the ungodly, and all needless connexions with those who are dead in sin; we must be zealous of good works devoted followers of God, and companions of his people.
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3-7. Whatsoever parteth the hoof, and is cloven-footed, and cheweth the cud—Ruminating animals by the peculiar structure of their stomachs digest their food more fully than others. It is found that in the act of chewing the cud, a large portion of the poisonous properties of noxious plants eaten by them, passes off by the salivary glands. This power of secreting the poisonous effects of vegetables, is said to be particularly remarkable in cows and goats, whose mouths are often sore, and sometimes bleed, in consequence. Their flesh is therefore in a better state for food, as it contains more of the nutritious juices, is more easily digested in the human stomach, and is consequently more easily assimilated. Animals which do not chew the cud, convert their food less perfectly; their flesh is therefore unwholesome, from the gross animal juices with which they abound, and is apt to produce scorbutic and scrofulous disorders. But the animals that may be eaten are those which "part the hoof as well as chew the cud," and this is another means of freeing the flesh of the animal from noxious substances. "In the case of animals with parted hoofs, when feeding in unfavorable situations a prodigious amount of f�tid matter is discharged, and passes off between the toes; while animals with undivided hoofs, feeding on the same ground, become severely affected in the legs, from the poisonous plants among the pasture" [Whitlaw, Code of Health]. All experience attests this, and accordingly the use of ruminating animals (that is, those which both chew the cud and part the hoof) has always obtained in most countries though it was observed most carefully by the people who were favored with the promulgation of God's law.