(3) When the hair in the plague is turned white.—Better, and the hair in the plagued spot, &c. The first symptom indicating the existence of the disorder is that the hair, which is generally jet-black among the Hebrews, turns white on the affected spot. The authorities during the second Temple defined it that there must at least be two hairs white, at the root and in the body of the bright spot, before the patient can be declared unclean. The word plague, in accordance with a usage common in Hebrew—to put the abstract for the concrete—denotes here the plagued spot, or the spot affected by the plague, whilst in Leviticus 13:4 it means the person affected by this disorder. Thus in Leviticus 19:32, “the hoary head” stands for hoary-headed person.

And the plague in sight be deeper than the skin.—Better, and the appearance of the plagued spot be deeper, &c. The second symptom which shows the development of the disorder is that the spot affected by this plague appears to be deeper than the rest of the skin.

Pronounce him unclean.—Literally, make him unclean. According to the frequently occurring phraseology a man is said to do that which in his official capacity he pronounces as done, or orders to be done. Thus Ezekiel is said “to destroy the city” when he simply foretold its destruction (Ezekiel 43:3). The existence of these two symptoms made it incumbent upon the priest to declare the person unclean, and hence imparting defilement.

Leviticus 13:3. The priest shall look on the plague — In some dubious cases, the priest might find it convenient to take the judgment of physicians, or of persons who understood the theory of diseases better than himself; but, as he was to admit to or exclude from the sanctuary, he alone was to give judgment, and pronounce who were clean or unclean, and, as such, to be admitted or excluded. When the hair is turned white — He begins with the last of the three marks of a leprosy, namely, the bright spot. The reason of the hair’s turning white is thus assigned by Calmet, in his Dissertation on the Leprosy: “The flesh,” says he, “ceasing to receive its proper nourishment from the blood, which gave it its former vivid colour, the hair, which has its root in the corrupted, empoverished glands, becomes likewise ill-nourished, and so grows whitish and slender, like a plant in stony, parched ground.” His flesh — For the leprosy consumed both the skin and the flesh.

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?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.

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. On the plague, i.e. the sign or appearance of the plague of leprosy. And it is observable, that the same signs of it are given by Moses here, and by the learned physicians in their works. And when the leprosy came to its height, not the hair only, but also the skin was turned white, as Exodus 4:6 Numbers 12:10. And this change of colour was an evidence both of the abundance of excrementitious humours, and of the weakness of nature, as we see in old and sick persons. Deeper than the skin; for the leprosy did consume both the skin and the flesh, as appears from 2 Kings 5:14.

Pronounce him unclean, Heb. make him unclean, i. e ministerially and declaratively, in which sense ministers are said to remit sins, Matthew 16:19, and to destroy nations, Jeremiah 1:10.

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.

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.