נגעים ט׳Negaim 9

Mishnah 1א׳

הַשְּׁחִין וְהַמִּכְוָה מִטַּמְּאִין בְּשָׁבוּעַ אֶחָד, בִּשְׁנֵי סִימָנִים, בְּשֵׂעָר לָבָן וּבְפִשְׂיוֹן. אֵיזֶה הוּא הַשְּׁחִין. לָקָה בְעֵץ אוֹ בְאֶבֶן אוֹ בְגֶפֶת אוֹ בְמֵי טְבֶרְיָא, כֹּל שֶׁאֵינוֹ מֵחֲמַת הָאֵשׁ, זֶה הוּא שְׁחִין. אֵיזוֹ הִיא מִכְוָה. נִכְוָה בְגַחֶלֶת אוֹ בְרֶמֶץ, כֹּל שֶׁהוּא מֵחֲמַת הָאֵשׁ, זוֹ הִיא מִכְוָה:

[The Negaim (diseased patches on skin, clothes, or houses that create impurity) within] a boil or burn make one impure after one week [maximum] through two signs: white hair or spreading. What is considered a boil? If he was wounded by wood or by stone or by [the heat generated by] crushed olives or the waters of [the hot springs of] Tiberius, [or] anything not because of a fire, this is considered a boil. What is considered a burn? [If] he was burnt by coals or by embers, [or] anything because of fire, this is considered a burn.

Mishnah 2ב׳

הַשְּׁחִין וְהַמִּכְוָה אֵין מִצְטָרְפִין זֶה עִם זֶה, וְאֵין פּוֹשִׂין מִזֶּה לָזֶה, וְאֵין פּוֹשִׂין לְעוֹר הַבָּשָׂר, וְלֹא עוֹר הַבָּשָׂר פּוֹשֶׂה לְתוֹכָן. הָיוּ מוֹרְדִין, טְהוֹרִין. עָשׂוּ קְרוּם כִּקְלִפַּת הַשּׁוּם, זוֹ הִיא צָרֶבֶת הַשְּׁחִין הָאֲמוּרָה בַתּוֹרָה. חָזְרוּ וְחָיוּ, אַף עַל פִּי שֶׁמְּקוֹמָן צַלֶּקֶת, נִדּוֹנִין כְּעוֹר הַבָּשָׂר:

[The Negaim within] a boil and a burn do not combine with each other [to make a Nega large enough to cause impurity], and do not spread from one to another, and do not spread to [normal] skin, and [normal] skin does not spread into them. If they were unhealed, they are pure [even with a Nega]. If they formed a membrane like the skin of garlic, this is the scab of the boil mentioned in the Torah. [If] they returned [to normal] and healed, even though their area is scarred, they are judged like [normal] skin.