[א] "וכי יראה הכהן את נגע הנתק" – אמר ר' שמעון מה ת"ל "נגע הנתק"? הקיש נגע לנתק, מה נגע, שיער לבן שבו אינו מטמא אלא הפוך, אף נתק שיער צהוב שבו לא יטמא אלא הפוך שיער צהב דק. 1) (Vayikra 13:31) ("And if the Cohein sees the nega of the nethek, and, behold, its appearance is not deeper than the skin, and there is no black hair in it, then the Cohein shall quarantine the nega of the nethek for seven days.") "And if the Cohein sees the nega of the nethek": R. Shimon says: What is the intent of this? Nethek is being likened to nega. Just as a nega confers tumah only if it precedes the white hair, so a nethek confers tumah only if it precedes the yellow hair.
[ב] ק"ו: ומה אם שיער לבן, שאין שיער אחר מציל מידו, אינו מטמא אלא הפוך, שיער צהוב דק שיש שער אחר מציל אינו דין שלא יטמא אלא הפוך?! לא אם אמרת בשער לבן שלא יפה כחו במקומו ליטמא בכל מראה, תאמר בשער צהוב דק שיפה כחו במקומו ליטמא בכל מראה? הואיל ויפה כחו במקומו ליטמא בכל מראה, יטמא הפוך ושלא הפוך. ת"ל "נגע נתק" – הקיש נגע לנתק, מה הנגע, שער לבן שבו אינו מטמא אלא הפוך אף הנתק – שיער צהוב שבו לא יטמא אלא הפוך. 2) (Now why is a verse needed for this?) Does it not follow a fortiori? viz.: If white hair, which other hair does not "rescue" (from conferring tumah [i.e., black hair in that site does not prevent the white hair from conferring tumah]) — (If white hair) confers tumah only if the nega precedes it, how much more so should thin yellow hair, which other hair does rescue (from conferring tumah [i.e., black hair in that site does prevent the yellow hair from conferring tumah) — (How much more so should yellow hair) confer tumah only if the nega precedes it! — No, (the verse is needed, for) this may be the case with white hair which is powerless in its place to confer tumah within (a nega of) any appearance, (but only in a nega of one of the four "appearances"), as opposed to thin yellow hair, which has the power in its place to confer tumah within (a nethek of) any appearance. And since this is the case, I would say that it confers tumah whether or not the nethek precedes it. It must, therefore, be written "the nega of the nethek." Nethek is being likened to nega. Just as a nega confers tumah only if it precedes the white hair, so a nethek confers tumah only if it precedes the yellow hair.
[ג] ר' יהודה אומר כל מקום שצריך לומר "הפך" אמר "הפך" אבל הנתק שנאמר בו "ושער צהב", מטמא הפוך ושלא הפוך. 3) R. Yehudah says: Wherever the stipulation of precedence (of nega to hair) must be made, it is made (explicitly, in the verse itself), but nethek, about which it is written (Vayikra 13:32) "and there is no yellow hair in it" (without any explicit stipulation of precedence), (nethek) confers tumah whether or not it precedes (the yellow hair).
[ד] א"כ למה נאמר "נגע נתק"? הקיש נתק לנגע, מה נגע אינו פחות מכגריס אף נתק כגריס. וכשהוא אומר למטה "נגע נתק" הקיש נגע לנתק, מה נתק שאין פשיון לתוכו אף נגע שאין הפשיון לתוכו. 4) Why, then, is it written the nega of the nethek? Nethek is being likened to nega. Just as nega does not (confer tumah) with less than a garis, so nethek does not (confer tumah) with less than a garis. And by the repetition of "the nega of the nethek" (Vayikra 13:32), nega is being likened to nethek. Just as there is no "spreading" into a nethek, so there is no "spreading" into a nega. (If there were a michyah in the midst of a bahereth and the bahereth spread into it, it is not called a "spreading" [for purposes of tumah]).
[ה] "ושיער" – מיעוט שער שתי שערות. "שחור" – אין לי אלא שחור, ומנין לרבות את הירוק ואת האדום? ת"ל "שער". א"כ למה נאמר שחור? שהשחור מציל והצהוב אינו מציל. 5) ("and there is no black hair in it") "hair": the minimum of "hair," two hairs. "black": This tells me only of black. Whence do I derive for inclusion green and red? From "and … hair." If so, why is it written "black"? Black "rescues" (from tumah if it appears before the nethek) and yellow does not "rescue" (from tumah if it appears before the nethek.)
[ו] איזהו צהוב שאינו מציל?…הרי שקדם את הנתק טמא דברי ר"י… אלא שהיו בו שתי שערות, אחת צהובה ואחת שחורה, אחת צהובה ואחת לבנה, הייתי אומר הואיל ואינן מצטרפין לטומאה יצטרפו לטהרה… ת"ל "שחור" – השחור מציל והצהוב אינו מציל. ראב"י אומר שיער צהוב שקדם את הנתק לא מטמא ולא מציל. ר' שמעון אומר כל שאינו סימן טומאה בנתק הרי הוא סימן טהרה בנתק. 6) For which "yellow hair" (do I need the verse to tell me that it does not "rescue"), according to the words of R. Yehudah, who holds (even without that verse) that (even) if yellow hair precedes the nethek it is tamei? (I need the verse for the following instance:) If there were two hairs, one yellow and one black, or one yellow and one white, I would think that since they do not combine for tumah, they do combine for taharah (i.e., to render the nethek tahor); it must, therefore, be written "and there is no black hair in it" — black ([two black hairs] in the above instance) rescues (from tumah); yellow does not rescue. R. Eliezer b. Yaakov says: Yellow hair which precedes the nethek neither confirms (tumah) nor rescues from it. R. Shimon says: Whatever is not a sign of tumah in a nethek is a sign of taharah in a nethek.
[ז] "אין בו" – עד שיהא מבוצר בו. מכאן אמרו ב' נתקים זה בצד זה ושיטה של שער מפסקת בינתים. נפרץ ממקום אחד – טמא. משני מקומות – טהור. כמה תהא פרצה? מקום שתי שערות. נפרץ ממקום אחד כגריס- טמא, מפני שלא כנס שער שחור לתוכו. 7) "there is not in it (the nethek) a black hair": "in it" — so that it (the black hair) is surrounded by it (the nethek. Only then is he tahor.) From here they ruled (Negaim 10:6): If there were two nethakim alongside each other, a column of hair separating them — If it (the column) were breached (with baldness) in one place, he is tamei, (for it must be that one of the nethakim has spread.) But if it were breached in two places (with two black hairs left in the middle), he is tahor, (for the two breaches are regarded as part of one nethek with two black hairs within it, which "rescue" him from tumah.) How large must each breach be, (for the two nethakim to be regarded as one, with black hair in the middle, and thus rescue him from tumah)? The size of two hairs. If it were breached (only) in one place, the size of a garis, he is tamei, (the black hair not being regarded as surrounded by the nega).
[ח] שני נתקים זה לפנים מזה ושיטה של שער מפסקת ביניהם. נפרץ ממקום אחד- טמא. משני מקומות טהור. כמה תהיה פרצה? מקום שתי שערות. נפרץ ממקום אחד כגריס טהור מפני שכנס שיער שחור לתוכו. 8) (If there were) two nethakim, one in the middle of the other, and a column (i.e., a circle) of (black) hair separating them (so that the outer circle is tahor and the inner one tamei) — If it (the column) were breached in one place, it (the inner nethek) is tamei (and the outer one tahor). (If it were breached) in two places, it (the inner [and, it goes without saying, the outer]) is tahor, (the two breaches causing the whole to be regarded as one nethek with the surrounded black hairs in its midst). How large must each breach be? The size of two hairs. If it were breached in one side the size of a garis it is tahor because it contains black hair within it.
[ט] "ושער שחור אין בו והסגיר" – ואם יש בו, פטור. או אינו אומר אלא "ושער שחור אין בו והסגיר" ואם יש בו טמא? כשהוא אומר "ואם בעיניו עמד הנתק… טהור הוא" הרי זה בא ללמד על שיער שחור שהוא סימן טהרה בנתק. הא מה אני מקיים ושער שחור אין בו"? – ואם יש בו פטור והסגיר הכהן את נגע הנתק שבעת ימים – תחילה. 9) "and there is no black hair in it, then he shall quarantine the nethek," but if there was (black hair) in it, he is exempt. — But perhaps the meaning is that in the absence of black hair he is to be quarantined, and in its presence, he is tamei! — This cannot be,) for (Vayikra 13:37) "And in his eyes the nethek has remained as it was, and black hair has sprouted in it … he is tahor" indicates that black hair is a sign of taharah in a nethek. How, then, am I to understand "and there is no black hair in it, etc."? (As meaning that) if there was (black hair), he is exempt. "then the Cohein shall quarantine the nega of the nethek for seven days.": This is the first quarantine.