נגעים ח׳Negaim 8

Mishnah 1א׳

הַפּוֹרֵחַ מִן הַטָּמֵא, טָהוֹר. חָזְרוּ בוֹ רָאשֵׁי אֵבָרִים, טָמֵא, עַד שֶׁתִּתְמַעֵט בַּהַרְתּוֹ מִכַּגְּרִיס. מִן הַטָּהוֹר, טָמֵא. חָזְרוּ בוֹ רָאשֵׁי אֵבָרִים, טָמֵא, עַד שֶׁתַּחֲזֹר בַּהַרְתּוֹ לִכְמוֹת שֶׁהָיְתָה:

[If a Nega (diseased patch on skin, clothes, or houses that creates impurity) completely] spreads over the impure [body], it becomes pure. [If] the tips of the limbs return [from being covered], it becomes impure until his Baheret [type of diseased patch that creates impurity] diminishes to less than [the size of] a bean. [If it spread over] the pure [body], it becomes impure. [If] the tips of the limbs return [from being covered], it becomes impure until his Baheret returns to what it was.

Mishnah 2ב׳

בַּהֶרֶת כַּגְּרִיס וּבָהּ מִחְיָה כָעֲדָשָׁה, פָּרְחָה בְכֻלּוֹ וְאַחַר כָּךְ הָלְכָה לָהּ הַמִּחְיָה, אוֹ שֶׁהָלְכָה לָהּ הַמִּחְיָה וְאַחַר כָּךְ פָּרְחָה בְכֻלּוֹ, טָהוֹר. נוֹלְדָה לוֹ מִחְיָה, טָמֵא. נוֹלַד לוֹ שֵׂעָר לָבָן, רַבִּי יְהוֹשֻׁעַ מְטַמֵּא, וַחֲכָמִים מְטַהֲרִין:

A Baheret like [the size of] a bean with a healthy patch of skin in it, if [the Baheret] spread over his entire [body] and afterwards the patch went away, or the patch went away and afterwards [the Baheret] spread over his entire [body], he becomes pure. If [subsequently] he develops a healthy patch of skin, he is impure. If he develops white hair, Rabbi Yehoshua declares impure but the Sages declare pure.