And, again, we find yet another analogy in the fact that, among the ancient Hebrews, the disease was regarded as _incurable_ by human means; and, notwithstanding occasional announcements in our day that a remedy has been discovered for the plague, this seems to be the verdict of the best authorities in medical science still. That in this respect leprosy perfectly represents the sorer malady of the soul, every one is witness. No possible effort of will or fixedness of determination has ever availed to free a man from sin. Even the saintliest Christian has often to confess with the Apostle Paul (Rom. vii. 19), "The evil which I would not, that I practise." Neither is culture, whether intellectual or religious, of any more avail. To this all human history testifies. In our day, despite the sad lessons of long experience, many are hoping for much from improved government, education, and such like means; but vainly, and in the face of the most patent facts. Legislation may indeed impose restrictions on the more flagrant forms of sin, even as it may be of service in restricting the devastations of leprosy, and ameliorating the condition of lepers. But to do away with sin, and abolish crime by any conceivable legislation, is a dream as vain as were the hope of curing leprosy by a good law or an imperial proclamation. Even the perfect law of God has proved inadequate for this end; the Apostle (Rom. viii. 3) reminds us that in this it has failed, and could not but fail, "in that it was weak through the flesh." Nothing can well be of more importance than that we should be keenly alive to this fact; that so we may not, through our present apparently tolerable condition, or by temporary alleviations of the trouble, be thrown off our guard, and hope for ourselves or for the world, upon grounds which afford no just reason for hope.
Last of all, the law of leprosy, as given in this chapter, teaches the supreme lesson, that as with the symbolic disease of the body, so with that of the soul, sin _shuts out from God and from the fellowship of the holy_. As the leper was excluded from the camp of Israel and from the tabernacle of Jehovah, so must the sinner, except cleansed, be shut out of the Holy City, and from the glory of the heavenly temple. What a solemnly significant parable is this exclusion of the leper from the camp! He is thrust forth from the congregation of Israel, wearing the insignia of mourning for the dead! Within the camp, the multitude of them that go to the sanctuary of God, and that joyfully keep holy day; without, the leper dwelling alone, in his incurable corruption and never-ending mourning! And so, while we do not indeed deny a sanitary intention in these regulations of the law, but are rather inclined to affirm it; yet of far more consequence is it that we heed the spiritual truth which this solemn symbolism teaches. It is that which is written in the Apocalypse (xxi. 27; xxii. 15) concerning the New Jerusalem: "There shall in no wise enter into it anything unclean.... Without are the dogs, and the sorcerers, and the fornicators, and the murderers, and the idolaters, and every one that loveth and maketh a lie."
In view of all these correspondences, one need not wonder that in the symbolism of the law leprosy holds the place which it does. For what other disease can be named which combines in itself, as a physical malady, so many of the most characteristic marks of the malady of the soul? In its intrinsic loathsomeness, its insignificant beginnings, its slow but inevitable progress, in the extent of its effects, in the insensibility which accompanies it, in its hereditary character, in its incurability, and, finally, in the fact that according to the law it involved the banishment of the leper from the camp of Israel,--in all these respects, it stands alone as a perfect type of sin; it is sin, as it were, made visible in the flesh.