Negaim, Chapter 1, Mishnah 1. With this mishnah we open a new masechta in Seder Taharos. Negaim is built on the parshiyos of Tazria and Metzora, and it treats the various plagues that the Torah calls tzara'as, loosely rendered as leprosy, though it is nothing of the sort medically. These are afflictions produced by a spiritual defect, and they demand a process of purification.
There are three broad categories. First, nig'ei adam, the plagues that appear on a person's skin, which themselves come in several forms. Second, nig'ei begadim, discolorations that break out on garments. Third, at the end of parshas Metzora, after the Torah finishes with the purification of the metzora himself, come nig'ei batim, plagues that strike a house.
Treasure in the ruins
Chazal teach, and Rashi brings it in Chumash, that the Emori knew Klal Yisroel were destined to conquer Eretz Yisroel, so they hid their wealth in the foundations of their homes. Years later a Jew would move into such a house, the house would break out in a nega, and when every earlier stage failed and the kohen finally ordered it torn down, the owner would discover a fortune buried in the rubble. The plague that seemed to be pure loss turned out to be the vehicle of great gain.
And what holds true for a stricken house holds true all the more for nig'ei adam. Someone marked by tzara'as is removed from the camp, obliged to keep others at a distance by announcing his state with the cry "tamei, tamei," and only when the affliction runs its course does he enter the process of becoming tahor again. Chazal hear in the word metzora an allusion to one who circulates an evil report about his neighbor. What ails such a person is a defect in middos, a tzarus ayin, a stinginess of vision when he looks at another Jew. The entire apparatus of nega'im exists to cleanse him and to lift him higher through what he is made to endure, and that is the wealth concealed inside his suffering.
The mishnah's opening statement
The mishnah plunges directly into nig'ei adam: "Maros nega'im shenayim shehein arba'ah," the appearances of nega'im are two, and those two are four. Two are the primary shades, and each carries a subcategory beneath it, so that in practice there are four.
Mishnah uses this pattern in other places as well. Masechta Shabbos organizes the forbidden labors as principal melachos with offshoots ranked under them, and Bava Kamma sorts liability into principal categories of nezikin together with their derivatives. Nega'im follows the identical scheme: two principals, and beneath each one a derivative.
Anyone studying nig'ei adam should have a Chumash open at Tazria, and afterwards at Metzora. Vayikra perek yud gimmel, posuk beis, lays out the case: "Adam ki yihyeh be'or besaro," when a person has upon the skin of his flesh one of three marks, a se'eis, or else a sapachas, or else a vaheres, "vehayah be'or besaro lenega tzara'as," and it develops on his skin into a plague of tzara'as, then "vehuva el Aharon HaKohen o el echad mibanav hakohanim," he is brought to Aharon HaKohen, or to one of the kohanim among his sons.
The posuk yields two lessons. The term sapachas carries the sense of something appended, something subordinate rather than primary, and it is precisely from this term that the derivative shades are learned. And the last words of the posuk establish a principle for the whole subject: pronouncing a nega tamei or tahor, on skin, on cloth or on a wall, is the exclusive province of a kohen.
Which white is higher and which is deeper
Rashi observes in his commentary on Chumash, in more than one place, that in shading with depth a lighter and more vivid tone reads to the eye as sunken, while a duller, dimmer tone reads as raised. The name se'eis comes from the root of lifting and rising, which tells us it is the fainter of the whites, leaving the baheres as the dazzling one.
How do we know that each of the two has its own sapachas? The Rav learns it from the placement of the word: sapachas is written in the middle, between se'eis and vaheres, so it attaches to both. There is one sapachas for se'eis and one sapachas for baheres.
The Tosfos Yom Tov quotes an alternative source, Toras Kohanim, which is the halachic Midrash of the Tannaim on Sefer Vayikra. Its reading assigns each term its place: the word se'eis refers to the primary se'eis, the word baheres to the primary baheres, and the sapachas of our posuk is understood as the shade ranked second to baheres. As for the derivative of se'eis, that is drawn from a different posuk, which speaks of the nega appearing sunken below the skin, "umar'eh hanega amok." Two distinct derivations, arriving at the same total of four.
The four shades themselves
The mishnah spells them out. The baheres is "azah kasheleg," a strong, brilliant white like snow, and "sheni lah kesid haheichal," its secondary shade is like the whitewash of the heichal. The heichal is the Kodesh, the chamber of the Beis HaMikdash beyond the ulam, the entrance hall past the azarah, with the Kodesh HaKodashim behind it. Every year, before Pesach, the walls of the heichal were whitewashed with a very bright limestone, and that shade of white is the standard the mishnah uses.
Regarding the se'eis, the first view recorded in the mishnah, which is Rabbi Meir's, identifies the se'eis itself as "kekerum beitzah," the shade of the thin film lining an eggshell, and rules that "sheni lah ketzemer lavan," the shade below it matches white wool. On this reading the derivative is actually the whiter of the two. The meforshim clarify that the wool in question is that of a lamb on the very day of its birth, once it has been cleaned, a white of remarkable purity. So teaches Rabbi Meir.
"Vachachamim omrim": the Chachamim invert the order. In their view the se'eis proper is the color of white wool, and the shade classed under it is that of the egg's membrane. Their disagreement is confined to the se'eis and its derivative; concerning baheres and its derivative there is no argument. The halacha is decided like the Chachamim, so that white wool serves as the principal shade with the egg membrane ranked beneath it.
So the Torah, which set out to purify a man from the narrowness of eye that brought his affliction, begins by teaching the kohen to look closely, to distinguish one white from another, and to see precisely what is in front of him.