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.

The plague of leprosy - This dreadful disorder has its name leprosy, from the Greek λεποα, from λεπις, a scale, because in this disease the body was often covered with thin white scales, so as to give it the appearance of snow. Hence it is said of the hand of Moses, Exo 4:6, that it was leprous as snow; and of Miriam, Num 12:10, that she became leprous, as white as snow; and of Gehazi, Kg2 5:27, that, being judicially struck with the disease of Naaman, he went out from Elisha's presence a leper as white as snow. See Clarke's note on Exo 4:6. In Hebrew this disease is termed צרעת tsaraath, from צרע mor tsara, to smite or strike; but the root in Arabic signifies to cast down or prostrate, and in Ethiopian, to cause to cease, because, says Stockius, "it prostrates the strength of man, and obliges him to cease from all work and labor." There were three signs by which the leprosy was known.

1.A bright spot.

2.A rising (enamelling) of the surface.

3.A scab; the enamelled place producing a variety of layers, or stratum super stratum, of these scales.

The account given by Mr. Maundrell of the appearance of several persons whom he saw infected with this disorder in Palestine, will serve to show, in the clearest light, its horrible nature and tendency. "When I was in the Holy Land," says he, in his letter to the Rev. Mr. Osborn, Fellow of Exeter College, "I saw several that labored under Gehazi's distemper; particularly at Sichem, (now Naplosu), there were no less than ten that came begging to us at one time. Their manner is to come with small buckets in their hands, to receive the alms of the charitable; their touch being still held infectious, or at least unclean. The distemper, as I saw it on them, was quite different from what I have seen it in England; for it not only defiles the whole surface of the body with a foul scurf, but also deforms the joints of the body, particularly those of the wrists and ankles, making them swell with a gouty scrofulous substance, very loathsome to look on. I thought their legs like those of old battered horses, such as are often seen in drays in England. The whole distemper, indeed, as it there appeared, was so noisome, that it might well pass for the utmost corruption of the human body on this side the grave. And certainly the inspired penman could not have found out a fitter emblem, whereby to express the uncleanness and odiousness of vice." - Maundrell's Travels. Letters at the end. The reader will do well to collate this account with that given from Dr. Mead; see the note on Exo 4:6 (note).

When a man shall have in the skin of his flesh,.... Rules are here given, by which a leprosy might be judged of; which, as a disease, was frequent in Egypt, where the Israelites had dwelt a long time, and from whence they were just come; and is doubtless the reason, as learned men have observed, that several Heathen writers make the cause of their expulsion from Egypt, as they choose to call it, though wrongly, their being infected with this distemper; whereas it was the reverse, not they, but the Egyptians, were incident to it (z). Moreover, the leprosy here spoken of seems not to be the same with that disease, or what we now call so, though some have thought otherwise; it being rather an uncleanness than a disease, and the business of a priest, and not a physician to attend unto; and did not arise from natural causes, but was from the immediate hand of God, and was inflicted on men for their sins, as the cases of Miriam, Gehazi, and Uzziah show; and who by complying with the rites and ceremonies hereafter enjoined, their sins were pardoned, and they were cleansed; so that as their case was extraordinary and supernatural, their cure and cleansing were as remarkable: besides, this impurity being in garments and houses, shows it to be something out of the ordinary way. And this law concerning it did not extend to all men, only to the Israelites, and such as were in connection with them, such as proselytes. It is said (a), all are defiled with the plague (of leprosy) except an idolater and a proselyte of the gate; and the commentators say (b), even servants, and little ones though but a day old; that is, they are polluted with it, and so come under this law. Now the place where this disorder appears is "in the skin of the flesh"; that is, where there is a skin, and that is seen; for there are some places, the Jewish writers (c) say, are not reckoned the skin of the flesh, or where that is not seen, and such places are excepted, and they are these; the inside of the eye, of the ear, and of the nose: wrinkles in the neck, under the pap, and under the arm hole; the sole of the foot, the nail, the head and beard: and this phrase, "in the skin of his flesh", is always particularly mentioned; and when there appeared in it

a rising, scab, or bright spot; the scab that is placed between the rising or swelling, and the bright spot, belongs to them both, and is a kind of an accessory, or second to each of them: hence the Jews distinguish the scab of the swelling, and the scab of the bright spot; so that these make four in all, as they observe (d). And to this agrees what Ben Gersom on this text remarks; the bright spot is, whose whiteness is as the snow; the rising or swelling is what is white, as the pure wool of a lamb of a day old; the scab is what is inferior in whiteness to the rising, and is as in the degree of the whiteness of the shell or film of an egg; and this is the order of these appearances, the most white is the bright spot, after that the rising, and after that the scab of the bright spot, and after that the scab of the rising or swelling; and, lo, what is in whiteness below the whiteness of this (the last) is not the plague of leprosy:

and it be in the skin of his flesh like the plague of leprosy; either of the above appearances in the skin, having somewhat in them similar to the leprosy, or which may justly raise a suspicion of it, though it is not clear and manifest:

then he shall be brought to Aaron the priest, or unto one of his sons the priests; for, as Jarchi notes, there was no pollution nor purification of the leprosy, but by the mouth or determination of a priest. And a good man that was desirous, and made conscience of observing the laws of God, when he observed anything of the above in him, and had any suspicion of his case, would of himself go, and show himself to the priest; but if a man did not do this, and any of his neighbours observed the appearances on him, brought him to the priest whether he would or not, according to the text:

he shall be brought: that is, as Aben Ezra explains it, whether with or without his will; for he that sees in him one of the signs, shall oblige him to come to the priest; and who observes, that by Aaron the priest is meant, the priest anointed in his room; and by his sons the priests, the common priests, who are found without the sanctuary; such as the priests of Anathoth, but who were not of those that were rejected.

(z) Est elephas morbus-----gignitur Aegypto. Lucret. l. 6. ver. 1112. (a) Misn. Negaim, c. 3. sect. 1. (b) Maimon. & Bartenora in ib. (c) Misn. Negaim. c. 6. sect. 8. & Maimon. & Bartenora in ib. (d) Misn. ib. c. 1. sect. 1.