Leviticus 13:4

The main purpose of isolating someone was to find out if a person was sick. It gave the priest time to watch the person’s symptoms.

a skin disease: The Hebrew word tsaraʿat refers to more than Hansen’s disease (leprosy), which is rare and severely disfiguring. In Leviticus, the word describes many different conditions. These include:

• an open sore (13:10),

• a boil (13:18),

• a burn (13:24),

• a sore on the head or chin (13:29),

• shiny white patches (13:38), or

• unusual baldness (13:40).

A key test was whether the condition spread to other parts of the body (13:5–8). If it did, they quarantined the person while the disorder lasted (13:46). Not only people, but also clothing and even buildings could become infected (13:47–59; 14:33–53).

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.

I. Concerning the plague of leprosy we may observe in general, 1. That it was rather an uncleanness than a disease; or, at least, so the law considered it, and therefore employed not the physicians but the priests about it. Christ is said to cleanse lepers, not to cure them. We do not read of any that died of the leprosy, but it rather buried them alive, by rendering them unfit for conversation with any but such as were infected like themselves. Yet there is a tradition that Pharaoh, who sought to kill Moses, was the first that ever was struck with this disease, and that he died of it. It is said to have begun first in Egypt, whence it spread into Syria. It was very well known to Moses, when he put his own hand into his bosom and took it out leprous. 2. That it was a plague inflicted immediately by the hand of God, and came not from natural causes, as other diseases; and therefore must be managed according to a divine law. Miriam's leprosy, and Gehazi's, and king Uzziah's, were all the punishments of particular sins: and, if generally it was so, no marvel there was so much care taken to distinguish it from a common distemper, that none might be looked upon as lying under this extraordinary token of divine displeasure but those that really were so. 3. That it is a plague not now known in the world; what is commonly called the leprosy is of a quite different nature. This seems to have been reserved as a particular scourge for the sinners of those times and places. The Jews retained the idolatrous customs they had learnt in Egypt, and therefore God justly caused this with some others of the diseases of Egypt to follow them. Yet we read of Naaman the Syrian, who was a leper, Kg2 5:1. 4. That there were other breakings-out in the body which did very much resemble the leprosy, but were not it, which might make a man sore and loathsome and yet not ceremonially unclean. Justly are our bodies called vile bodies, which have in them the seeds of so many diseases, by which the lives of so many are made bitter to them. 5. That the judgment of it was referred to the priests. Lepers were looked upon as stigmatized by the justice of God, and therefore it was left to his servants the priests, who might be presumed to know his mark best, to pronounce who were lepers and who were not. All the Jews say, "Any priest, though disabled by a blemish to attend the sanctuary, might be a judge of the leprosy, provided the blemish were not in his eye. And he might" (they say) "take a common person to assist him in the search, but the priest only must pronounce the judgment." 6. That it was a figure of the moral pollution of men's minds by sin, which is the leprosy of the soul, defiling to the conscience, and from which Christ alone can cleanse us; for herein the power of his grace infinitely transcends that of the legal priesthood, that the priest could only convict the leper (for by the law is the knowledge of sin), but Christ can cure the leper, he can take away sin. Lord, if thou wilt, thou canst make me clean, which was more than the priests could do, Mat 8:2. Some think that the leprosy signified, not so much sin in general as a state of sin, by which men are separated from God (their spot not being the spot of God's children), and scandalous sin, for which men are to be shut out from the communion of the faithful. It is a work of great importance, but of great difficulty, to judge of our spiritual state: we have all cause to suspect ourselves, being conscious to ourselves of sores and spots, but whether clean or unclean is the question. A man might have a scab (Lev 13:6) and yet be clean: the best have their infirmities; but, as there were certain marks by which to know that it was a leprosy, so there are characters of such as are in the gall of bitterness, and the work of ministers is to declare the judgment of leprosy and to assist those that suspect themselves in the trial of their spiritual state, remitting or retaining sin. And hence the keys of the kingdom of heaven are said to be given to them, because they are to separate between the precious and the vile, and to judge who are fit as clean to partake of the holy things and who as unclean must be debarred from them.
II. Several rules are here laid down by which the judgment of the priest must be governed. 1. If the sore was but skin-deep, it was to be hoped it was not the leprosy, Lev 13:4. But, if it was deeper than the skin, the man must be pronounced unclean, Lev 13:3. The infirmities that consist with grace do not sink deep into the soul, but the mind still serves the law of God, and the inward man delights in it, Rom 7:22, Rom 7:25. But if the matter be really worse than it shows, and the inwards be infected, the case is dangerous. 2. If the sore be at a stay, and do not spread, it is no leprosy, Lev 13:4, Lev 13:5. But if it spread much abroad, and continue to do so after several inspections, the case is bad, Lev 13:7, Lev 13:8. If men do not grow worse, but a stop be put to the course of their sins and their corruptions be checked, it is to be hoped they will grow better; but if sin get ground, and they become worse every day, they are going downhill. 3. If there was proud raw flesh in the rising, the priest needed not to wait any longer, it was certainly a leprosy, Lev 13:10, Lev 13:11. Nor is there any surer indication of the badness of a man's spiritual state than the heart's rising in self-conceit, confidence in the flesh, and resistance of the reproofs of the word and strivings of the Spirit. 4. If the eruption, whatever it was, covered all the skin from head to foot, it was no leprosy (Lev 13:12, Lev 13:13); for it was an evidence that the vitals were sound and strong, and nature hereby helped itself, throwing out what was burdensome and pernicious. There is hope in the small-pox when they come out well: so if men freely confess their sins, and hide them not, there is no danger comparable to theirs that cover their sins. Some gather this from it, that there is more hope of the profane than of hypocrites. The publicans and harlots went into the kingdom of heaven before scribes and Pharisees. In one respect, the sudden breakings-out of passion, though bad enough, are not so dangerous as malice concealed. Others gather this, that, if we judge ourselves, we shall not be judged; if we see and own that there is no health in us, no soundness in our flesh, by reason of sin, we shall find grace in the eyes of the Lord. 5. The priest must take time in making his judgment, and not give it rashly. If the matter looked suspicious, he must shut up the patient seven days, and then seven days more, that his judgment might be according to truth. This teaches all, both ministers and people, not to be hasty in their censures, nor to judge any thing before the time. If some men's sins go before unto judgment, the sins of others follow after, and so men's good works; therefore let nothing be done suddenly, Ti1 5:22, Ti1 5:24, Ti1 5:25. 6. If the person suspected was found to be clean, yet he must wash his clothes (Lev 13:6), because he had been under the suspicion, and there had been in him that which gave ground for the suspicion. Even the prisoner that is acquitted must go down on his knees. We have need to be washed in the blood of Christ from our spots, though they be not leprosy-spots; for who can say, I am pure from sin? though there are those who through grace are innocent from the great transgression.

When a man shall have in the skin. Since every eruption was not the leprosy, and did not render a man unclean, when God appoints the priests to be the judges, He distinguishes by certain marks a common eruption from the leprosy; and then subjoins the difference between the various kinds of leprosy. For the disease was not always incurable; but, only when the blood was altogether corrupted, so that the skin itself had become hardened by its corrosion, or swollen by its diseased state. This, then, must be observed in the first place, that the Greek and Latin word lepra, and the Hebrew tsrt tzaragmath, extend further than to the incurable disease, which medical men call elephantiasis [4] both on account of the hardness of the skin, and also its mottled color; not, however, that there is an entire agreement between the thickness of the man's skin and that of an elephant, but because this disease produces insensibility of the skin. This the Greeks call Psora, and if it be not a kind of leprosy, it is nearly allied to it. Thus we see that there was a distinction between the scab and leprosy; just as now-a-days, if it were necessary to judge respecting the itch, (which is commonly called the disease of St. Menanus, [5] the marks must be observed, which distinguish it from leprosy. But, as to the various kinds of leprosy, I confess that I am not a physician, so as to discuss them accurately, and I purposely abstain from close inquiry about them, because I am persuaded that the disease here treated of affected the Israelites in an extraordinary manner, which we are now unacquainted with; for what do we now know of a leprous house? Indeed it is probable that, since heathen writers knew that the Jewish people suffered from this disease, they laid hold of it as the ground of their falsehood, that all the descendants of Abraham were infected with the itch, and were driven away from Egypt, lest others should catch it from them. That [6] this was an ancient calumny appears from Josephus, both in the ninth book of his Antiquities, and in his Treatise against Apion; and it is repeated both by C. Tacitus and Justin. Yet I make no doubt that the Egyptians, a very proud nation, in order to efface the memory of their own disgrace, and of the vengeance inflicted upon them by God, invented this lie, and thus grossly turned against this innocent people what had happened to themselves, when they were smitten with boils and blains. But we shall see hereafter, amongst God's curses, that He chastised His people with the same plagues as He had inflicted on the Egyptians:

"The Lord will smite thee with the botch of Egypt, and with the emerods, and with the scab," etc. (Deuteronomy 28:27.)

Whence it may be probably inferred, that God avenged the crimes of His ancient people with special judgments, which are now unknown to us; just as afterwards new diseases arose, from which those in old times were free. At any rate, Josephus, by clear and solid arguments, exposes the absurdity of this accusation, that Moses was driven from Egypt with a crowd of exiles, lest they should infect the country with their disease; because, if they had been universally affected with this malady, he never would have imposed such severe laws for separating the lepers from general society.

God first commands that, whenever a suspicion of leprosy arose, the man was to present himself to the priest; if any symptom of leprosy appeared, He commands him to be shut up for a period of seven days, until it should appear from the progress of the disease that it was incurable leprosy. That God should have appointed the priests to be judges, and those, too, only of the highest order, is a proof that His spiritual service was rather regarded than mere bodily health. If any shall inquire whether leprosy is not a contagious disease, and whether it be not therefore expedient that all who were affected by it should be removed from intercourse with others, I admit, indeed, that such is the case, but I deny that this was the main object in view. For, in process of time, physicians would have been better able to decide by their art and skill: whereas God enjoined this decision upon the priests alone, and gave them the rule whereby they were to judge. Nor did He appoint the Levites indiscriminately, but only the sons of Aaron, who were the highest order, in order that the authority of the decision might be greater. It was, then, by a gross error, or rather impudence, that the Papal priests (sacrifici) assumed to themselves this jurisdiction. It was (they say) the office of the chief priests under the Law to distinguish between the kinds of leprosy; and, therefore, the same right is transferred to the bishops. But they carry the mockery still further: the official [7] the bishop's representative, sits as the legitimate judge; he calls in physicians and surgeons, from whose answers he pronounces what he confesses he is ignorant of himself. Behold how cleverly they accommodate a legal rite to our times! The mockery, however, is still more disgusting, when in another sense they extend to the whole tribe of priests what they have said to belong solely to the bishops; for, since the sin under which all labor is a spiritual leprosy, they thence infer that all are excluded from the congregation of the faithful until they shall have been purged and received by absolution, which they hold to be the common office of all the priests. They afterwards add, that judgment cannot be pronounced till the cause is heard, and so conclude that confession is necessary. But, if they choose to have recourse to subtleties, reason would rather conduct us to the opposite conclusion; for God did not desire the priests to take cognizance of a hidden disease, but only after the manifest symptoms had appeared: hence it will follow, that it is preposterous to bring secret sins to judgment, and that wretched men are dragged to their confession contrary to all law and justice. But, setting aside all these absurdities, an analogy must be observed between us and God's ancient people. He of old forbade the external uncleanness of the flesh to be tolerated in His people. By Christ's coming, the typical. figure has ceased; but we are taught that all uncleanness, whereby the purity of His services is defiled, is not to be cherished, or borne with amongst us. And surely excommunication answers to this ceremony; since by it the Church is purified, lest corruptions should everywhere assail it, if wicked and guilty persons occupied a place in it promiscuously with the good. The command of God that, whilst the disease was obscure and questionable, the infected person should be shut up for seven days, recommends moderation to us, lest any, who is still curable, should be condemned before his time. In fact, this medium is to be observed, that the judge should not be too remiss and hasty in pardoning, and still that he should temper severity by justice; and especially that he should not be too precipitate in his judgment. What we translate "shall pronounce him clean, or unclean," is in Hebrew, "shall clean, or unclean him;" thus the dignity of the judgment is more fully established, as though it had proceeded from God Himself; and assuredly no medical skill could declare on the seventh day a leprosy to be incurable, respecting which there was doubt so short a time before, unless God should in some special manner discover the uncleanness, and guide the eyes of the priests by His Spirit.

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 Lev 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 Mat 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.

If the bright spot be white in the skin of his flesh,.... The Targum of Jonathan is, white as chalk in the skin of his flesh; but other Jewish writers make the whiteness of the bright spot to be the greatest of all, like that of snow; See Gill on Leviticus 13:2,

and in sight be not deeper than the skin, and the hair thereof be not turned white; though it be a bright spot, and be very white, yet these two marks not appearing, it cannot be judged a leprosy, at most it is only suspicious: wherefore

then the priest, shall shut up him that hath the plague seven days; in whom the bright spot is, and of whom there is a suspicion of the plague of leprosy, but it is not certain; and therefore, in order to take time, and get further knowledge, the person was to be shut up from all company and conversation for the space of seven days; by which time it might be supposed, as Ben Gersom observes, that the case and state of the leprosy (if it was one) would be altered; and Aben Ezra remarks, that most diseases change or alter on the seventh day.

For greater assurance; to teach ministers not to be rash nor hasty in their judgments and censures, but diligently to search and examine all things beforehand.

The plague is here put for the man that hath the plague, as pride is put for a proud man, , and dreams for the dreamers, .

The symptoms of leprosy, whether proceeding directly from eruptions in the skin, or caused by a boil or burn. - Lev 13:2-8. The first case: "When a man shall have in the skin of his flesh (body) a raised spot or scab, or a bright spot." שׂאת, a lifting up (Gen 4:7, etc.), signifies here an elevation of the skin in some part of the body, a raised spot like a pimple. ספּחת, an eruption, scurf, or scab, from ספח to pour out, "a pouring out as it were from the flesh or skin" (Knobel). בּהרת .)le, from בּהר, in the Arabic and Chaldee to shine, is a bright swollen spot in the skin. If ether of these signs became "a spot of leprosy," the person affected was to be brought to the priest, that he might examine the complaint. The term zaraath, from an Arabic word signifying to strike down or scourge, is applied to leprosy as a scourge of God, and in the case of men it always denotes the white leprosy, which the Arabs call baras. נגע, a stroke (lit., "stroke of leprosy"), is applied not only to the spot attacked by the leprosy, the leprous mole (Lev 13:3, Lev 13:29-32, Lev 13:42, etc.), but to the persons and even to things affected with leprosy (Lev 13:4, Lev 13:12, Lev 13:13, Lev 13:31, Lev 13:50, Lev 13:55).
Lev 13:3
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.
Lev 13:4-6
But if the bright spot was white upon the skin, and its appearance was not deeper than the skin, and the place therefore was not sunken, nor the hair turned white, the priest was to shut up the leper, i.e., preclude him from intercourse with other men, for seven days, and on the seventh day examine him again. If he then found that the mole still stood, i.e., remained unaltered, "in his eyes," or in his view, that it had not spread any further, he was to shut him up for seven days more. And if, on further examination upon the seventh day, he found that the mole had become paler, had lost its brilliant whiteness, and had not spread, he was to declare him clean, for it was a scurf, i.e., a mere skin eruption, and not true leprosy. The person who had been pronounced clean, however, was to wash his clothes, to change himself from even the appearance of leprosy, and then to be clean.
Lev 13:7-8
But if the scurf had spread upon the skin "after his (first) appearance before the priest with reference to his cleansing," i.e., to be examined concerning his purification; and if the priest notice this on his second appearance, he was to declare him unclean, for in that case it was leprosy.
Lev 13:9-17
The second case (Lev 13:9-17): if the leprosy broke out without previous eruptions.
Lev 13:9-11
"If a mole of leprosy is in a man, and the priest to whom he is brought sees that there is a white rising in the skin, and this has turned the hair white, and there is raw (proud) flesh upon the elevation, it is an old leprosy." The apodosis to Lev 13:9 and Lev 13:10 commences with Lev 13:11. חי בּשׂר living, i.e., raw, proud flesh. מחיה the preservation of life (Gen 45:5), sustenance (Jdg 6:4); here, in Lev 13:10 and Lev 13:24, it signifies life in the sense of that which shows life, not a blow or spot (נגע, from מחה to strike), as it is only in a geographical sense that the verb has this signification, viz., to strike against, or reach as far as (Num 34:11). If the priest found that the evil was an old, long-standing leprosy, he was to pronounce the man unclean, and not first of all to shut him up, as there was no longer any doubt about the matter.
Lev 13:12-13
If, on the other hand, the leprosy broke out blooming on the skin, and covered the whole of the skin from head to foot "with regard to the whole sight of the eyes of the priest," i.e., as far as his eyes could see, the priest was to pronounce the person clean. "He has turned quite white," i.e., his dark body has all become white. The breaking out of the leprous matter in this complete and rapid way upon the surface of the whole body was the crisis of the disease; the diseased matter turned into a scurf, which died away and then fell off.
Lev 13:14-19
"But in the day when proud flesh appears upon him, he is unclean,...the proud flesh is unclean; it is leprosy." That is to say, if proud flesh appeared after the body had been covered with a white scurf, with which the diseased matter had apparently exhausted itself, the disease was not removed, and the person affected with it was to be pronounced unclean.
The third case: if the leprosy proceeded from an abscess which had been cured. In Lev 13:18 בּשׂר is first of all used absolutely, and then resumed with בּו, and the latter again is more closely defined in בּעורו: "if there arises in the flesh, in him, in his skin, an abscess, and (it) is healed, and there arises in the place of the abscess a white elevation, or a spot of a reddish white, he (the person so affected) shall appear at the priest's."
Lev 13:20
If the priest found the appearance of the diseased spot lower than the surrounding skin, and the hair upon it turned white, he was to pronounce the person unclean. "It is a mole of leprosy: it has broken out upon the abscess."
Lev 13:21-23
But if the hair had not turned white upon the spot, and there was no depression on the skin, and it (the spot) was pale, the priest was to shut him up for seven days. If the mole spread upon the skin during this period, it was leprosy; but if the spot stood in its place, and had not spread, it was השּׁחין צרבת, "the closing of the abscess:" literally "the burning;" here, that part of the skin or flesh which has been burnt up or killed by the inflammation or abscess, and gradually falls off as scurf (Knobel).
Lev 13:24-28
The fourth case (Lev 13:24-28): if there was a burnt place upon the skin of the flesh (מבות־אשׁ, a spot where he had burnt himself with fire, the scar of a burn), and the "life of the scar" - i.e., the skin growing or forming upon the scar (see Lev 13:10), - "becomes a whitish red, or white spot," i.e., if it formed itself into a bright swollen spot. This was to be treated exactly like the previous case. המּכוה שׂאת (Lev 13:28), rising of the scar of the burn, i.e., a rising of the flesh and skin growing out of the scar of the burn.