Command the children of Israel, that they put out of the camp every leper, and every one that hath an issue, and whosoever is defiled by the dead:

Jamieson-Fausset-Brown Bible Commentary

2. Command the children of Israel, that they put out of the camp every leper-The exclusion of leprous persons from the camp in the wilderness, as from cities and villages afterwards, was a sanitary measure taken according to prescribed rules (Le 13:1-14:57). This exclusion of lepers from society has been acted upon ever since; and it affords almost the only instance in which any kind of attention is paid in the East to the prevention of contagion. The usage still more or less prevails in the East among people who do not think the least precaution against the plague or cholera necessary; but judging from personal observation, we think that in Asia the leprosy has now much abated in frequency and virulence. It usually appears in a comparatively mild form in Egypt, Palestine, and other countries where the disorder is, or was, endemic. Small societies of excluded lepers live miserably in paltry huts. Many of them are beggars, going out into the roads to solicit alms, which they receive in a wooden bowl; charitable people also sometimes bring different articles of food, which they leave on the ground at a short distance from the hut of the lepers, for whom it is intended. They are generally obliged to wear a distinctive badge that people may know them at first sight and be warned to avoid them. Other means were adopted among the ancient Jews by putting their hand on their mouth and crying, "Unclean, unclean" [Le 13:45]. But their general treatment, as to exclusion from society, was the same as now described. The association of the lepers, however, in this passage, with those who were subject only to ceremonial uncleanness, shows that one important design in the temporary exile of such persons was to remove all impurities that reflected dishonor on the character and residence of Israel's King. And this vigilant care to maintain external cleanliness in the people was typically designed to teach them the practice of moral purity, or cleansing themselves from all filthiness of the flesh and spirit. The regulations made for ensuring cleanliness in the camp suggest the adoption of similar means for maintaining purity in the church. And although, in large communities of Christians, it may be often difficult or delicate to do this, the suspension or, in flagrant cases of sin, the total excommunication of the offender from the privileges and communion of the church is an imperative duty, as necessary to the moral purity of the Christian as the exclusion of the leper from the camp was to physical health and ceremonial purity in the Jewish church.

Matthew Henry's Concise Commentary

5:1-10 The camp was to be cleansed. The purity of the church must be kept as carefully as the peace and order of it. Every polluted Israelite must be separated. The wisdom from above is first pure, then peaceable. The greater profession of religion any house or family makes, the more they are obliged to put away iniquity far from them. If a man overreach or defraud his brother in any matter, it is a trespass against the Lord, who strictly charges and commands us to do justly. What is to be done when a man's awakened conscience charges him with guilt of this kind, though done long ago? He must confess his sin, confess it to God, confess it to his neighbour, and take shame to himself; though it go against him to own himself in a lie, yet he must do it. Satisfaction must be made for the offence done to God, as well as for the loss sustained by the neighbour; restitution in that case is not enough without faith and repentance. While that which is wrongly gotten is knowingly kept, the guilt remains on the conscience, and is not done away by sacrifice or offering, prayers or tears; for it is the same act of sin persisted in. This is the doctrine of right reason, and of the word of God. It detects hypocrites, and directs the tender conscience to proper conduct, which, springing from faith in Christ, will make way for inward peace.