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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31-35. whosoever doth touch them, when … dead, shall be unclean until the even—These regulations must have often caused annoyance by suddenly requiring the exclusion of people from society, as well as the ordinances of religion. Nevertheless they were extremely useful and salutary, especially as enforcing attention to cleanliness. This is a matter of essential importance in the East, where venomous reptiles often creep into houses and are found lurking in boxes, vessels, or holes in the wall; and the carcass of one of them, or a dead mouse, mole, lizard, or other unclean animal, might be inadvertently touched by the hand, or fall on clothes, skin bottles, or any article of common domestic use. By connecting, therefore, the touch of such creatures with ceremonial defilement, which required immediately to be removed, an effectual means was taken to prevent the bad effects of venom and all unclean or noxious matter.