To make a difference between the unclean and the clean, and between the beast that may be eaten and the beast that may not be eaten.

Jamieson-Fausset-Brown Bible Commentary

47. make a difference between the unclean and the clean-that is, between animals used and not used for food. It is probable that the laws contained in this chapter were not entirely new, but only gave the sanction of divine enactment to ancient usages. Some of the prohibited animals have, on physiological grounds, been everywhere rejected by the general sense or experience of mankind; while others may have been declared unclean from their unwholesomeness in warm countries or from some reasons, which are now imperfectly known, connected with contemporary idolatry.

Matthew Henry's Concise Commentary

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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