The hair in the plague is turned white - The sparing growth of very fine whitish hair on leprous spots in the place of the natural hair, appears to have been always regarded as a characteristic symptom.

the plague in sight be deeper than the skin of his flesh - Rather The stroke appears to be deeper than the scarf skin. The bright spot changed to a brownish color with a metallic or oily luster, and with a clearly-defined edge. This symptom, along with the whitish hair, at once decided the case to be one of leprosy.

The priest shall - pronounce him unclean - וטמא אתו vetimme otho; literally, shall pollute him, i. e., in the Hebrew idiom, shall declare or pronounce him polluted; and in Leviticus 13:23, it is said, the priest shall pronounce him clean, וטהרו הכהן vetiharo haccohen, the priest shall cleanse him, i. e., declare him clean. In this phrase we have the proper meaning of Matthew 16:19 : Whatsoever ye bind on earth, shall be bound in heaven; and whatsoever ye loose on earth shall be loosed in heaven. By which our Lord intimates that the disciples, from having the keys, i. e., the true knowledge of the doctrine, of the kingdom of heaven, should, from particular evidences, be at all times able to distinguish between the clean and the unclean, the sincere and the hypocrite; and pronounce a judgment as infallible as the priest did in the case of the leprosy, from the tokens already specified. And as this binding and loosing, or pronouncing fit or unfit for fellowship with the members of Christ, must in the case of the disciples be always according to the doctrine of the kingdom of heaven, the sentence should be considered as proceeding immediately from thence, and consequently as Divinely ratified. The priest polluted or cleansed, i. e., declared the man clean or unclean, according to signs well known and infallible. The disciples or ministers of Christ bind or loose, declare to be fit or unfit for Church fellowship, according to unequivocal evidences of innocence or guilt. In the former case, the priest declared the person fit or unfit for civil society; in the latter, the ministers of Christ declare the person against whom the suspicion of guilt is laid, fit or unfit for continued association with the Church of God. The office was the same in both, a declaration of the truth, not from any power that they possessed of cleansing or polluting, of binding or of loosing, but by the knowledge they gained from the infallible signs and evidences produced on the respective cases.

And the priest shall look on the plague in the skin of the flesh,.... Whether it be a swelling, scab, or a bright spot that appears, and judge of it by the following rules, and none but a priest might do this:

and when the hair in the plague is turned white; it arising in a place where hair grows, and which hair is not naturally white, but of another colour, but changed through the force of the plague; and there were to be two hairs at least, which were at first black, but turned white; so Jarchi and Ben Gersom: and these hairs, according to the Misnah (e), must be white at bottom; if the root (or bottom) is black, and the head (or top) white, he is clean; if the root white, and the head black, he is defiled; for hairs turning white is a sign of a disorder, of weakness, of a decay of nature, as may be observed in ancient persons:

and the plague in sight be deeper than the skin of his flesh; appears plainly to view to be more than skin deep, to have corroded and eat into the flesh below the skin:

it is a plague of leprosy; when these two signs were observed, hair turned white, and the plague was more than skin deep, then it was a plain case that it was the leprosy of which See Gill on Matthew 8:2, Matthew 8:3, Luke 5:12. This was an emblem of sin, and the corruption of nature, which is an uncleanness, and with which every man is defiled, and which renders him infectious, nauseous, and abominable; and of which he is only to be cured and cleansed by Christ, the great High Priest, through his blood, which cleanses from all sin. The above signs and marks of leprosy may be observed in this; the white hair denoting a decay of strength, see Hosea 7:9 may be seen in sinners, as in the leper, who are without moral and spiritual strength to keep the law of God, to do anything that is spiritually good, to regenerate, renew, convert, and sanctify themselves, or to bring themselves out of the state of pollution, bondage, and misery, in which they are; and, like the leprosy, sin lies deep in man; it is in his flesh, in which dwells no good thing, and in which there is no soundness; it does not lie merely in outward actions, but it is in the heart, which is desperately wicked; for the inward part of man is very wicked:

and the priest shall look on him, and pronounce him unclean; and so should be obliged to rend his clothes, make bare his head, put a covering on his upper lip, and cry, unclean, unclean; dwell alone without the camp, and at a proper time bring the offering for his cleansing, and submit to the several rites and ceremonies prescribed, Leviticus 13:45.

(e) Negaim, c. 4. sect. 4.

A person so diseased was to be pronounced unclean, (a) if the hair of his head had turned white on the mole, i.e., if the dark hair which distinguished the Israelites had become white; and (b) if the appearance of the mole was deeper than the skin of the flesh, i.e., if the spot, where the mole was, appeared depressed in comparison with the rest of the skin. In that case it was leprosy. These signs are recognised by modern observers (e.g., Hensler); and among the Arabs leprosy is regarded as curable if the hair remains black upon the white spots, but incurable if it becomes whitish in colour.

And the priest shall look on the plague in the skin of the flesh: and when the hair in the plague is turned white, and the plague in sight be {b} deeper than the skin of his flesh, it is a plague of leprosy: and the priest shall look on him, and pronounce him unclean.

(b) That is, shrunken in, and be lower than the rest of the skin.

13:3 When the hair is turned white - This change of colour was an evidence both of the abundance of excrementious humours, and of the weakness of nature, as we see in old and sick persons. His flesh - For the leprosy consumed both the skin and the flesh.

[2] priest

Some have found in the regulations of this chapter concerning an inquest by the priest of a case of leprosy, elaborate provisions for the exercise of discipline in the local church. No little self-righteousness and cruelty have come in thereby. The explicit instructions of the N.T. are the alone and sufficient rule of discipline.

3-6. the priest shall look on the plague in the skin of the flesh, &c.-The leprosy, as covering the person with a white, scaly scurf, has always been accounted an offensive blemish rather than a serious malady in the East, unless when it assumed its less common and malignant forms. When a Hebrew priest, after a careful inspection, discovered under the cutaneous blemish the distinctive signs of contagious leprosy, the person was immediately pronounced unclean, and is supposed to have been sent out of the camp to a lazaretto provided for that purpose. If the symptoms appeared to be doubtful, he ordered the person to be kept in domestic confinement for seven days, when he was subjected to a second examination; and if during the previous week the eruption had subsided or appeared to be harmless, he was instantly discharged. But if the eruption continued unabated and still doubtful, he was put under surveillance another week; at the end of which the character of the disorder never failed to manifest itself, and he was either doomed to perpetual exclusion from society or allowed to go at large. A person who had thus been detained on suspicion, when at length set at liberty, was obliged to "wash his clothes," as having been tainted by ceremonial pollution; and the purification through which he was required to go was, in the spirit of the Mosaic dispensation, symbolical of that inward purity it was instituted to promote.

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?