2 "When someone has a swelling or a blister or a shiny spot on the skin that might signal a serious skin disease on the body, bring him to Aaron the priest or to one of his priest sons. 3 The priest will examine the sore on the skin. If the hair in the sore has turned white and the sore appears more than skin deep, it is a serious skin disease and infectious. After the priest has examined it, he will pronounce the person unclean. 4 "If the shiny spot on the skin is white but appears to be only on the surface and the hair has not turned white, the priest will quarantine the person for seven days. 5 On the seventh day the priest will examine it again; if, in his judgment, the sore is the same and has not spread, the priest will keep him in quarantine for another seven days. 6 On the seventh day the priest will examine him a second time; if the sore has faded and hasn't spread, the priest will declare him clean - it is a harmless rash. The person can go home and wash his clothes; he is clean. 7 But if the sore spreads after he has shown himself to the priest and been declared clean, he must come back again to the priest 8 who will conduct another examination. If the sore has spread, the priest will pronounce him unclean - it is a serious skin disease and infectious.
Matthew Henry's Commentary on Leviticus 13:2-8
Commentary on Leviticus 13:1-17
(Read Leviticus 13:1-17)
The plague of leprosy was an uncleanness, rather than a disease. Christ is said to cleanse lepers, not to cure them. Common as the leprosy was among the Hebrews, during and after their residence in Egypt, we have no reason to believe that it was known among them before. Their distressed state and employment in that land must have rendered them liable to disease. But it was a plague often inflicted immediately by the hand of God. Miriam's leprosy, and Gehazi's, and king Uzziah's, were punishments of particular sins; no marvel there was care taken to distinguish it from a common distemper. The judgment of it was referred to the priests. And it was a figure of the moral pollutions of men's minds by sin, which is the leprosy of the soul, defiling to the conscience, and from which Christ alone can cleanse. The priest could only convict the leper, (by the law is the knowledge of sin,) but Christ can cure the sinner, he can take away sin. It is a work of great importance, but of great difficulty, to judge of our spiritual state. We all have cause to suspect ourselves, being conscious of sores and spots; but whether clean or unclean is the question. As there were certain marks by which to know it was leprosy, so there are marks of such as are in the gall of bitterness. The priest must take time in making his judgment. This teaches all, both ministers and people, not to be hasty in censures, nor to judge anything before the time. If some men's sins go before unto judgment, the sins of others follow after, and so do men's good works. If the person suspected were found to be clean, yet he must wash his clothes, because there had been ground for the suspicion. We have need to be washed in the blood of Christ from our spots, though not leprosy spots; for who can say, I am pure from sin?