Negaim 10:1-2

Negaim 10:1

A nega of the hair or beard can be rendered unclean for two weeks by two signs: thin yellow hair and spreading. Rabbi Akiva says that thin yellow hair means withered and short; Rabbi Yochanan ben Nuri said even if it’s long. Rabbi Yochanan ben Nuri supported his opinion by asking what people mean when they say that a stick or a reed is thin: it doesn’t only mean withered and short, it also means withered and long. Rabbi Akiva replied that before we learn from sticks, we should learn from hair: when people say that someone’s hair is thin, they mean withered and short, not withered and long.

Negaim 10:2

Rabbi Yehuda says that thin yellow hair causes ritual impurity whether it’s all gathered together in one place or dispersed, whether it’s surrounded by the nega or not, and whether it arrived after the nega or before it. Rabbi Shimon says that it only causes impurity when it came after the nega. Rabbi Shimon asked: doesn’t it make sense that if white hair – against which other hair provides no protection – causes impurity only when it comes after the nega, that thin yellow hair – against which other hair does provide protection – only cause impurity when it comes after the nega? Rabbi Yehuda replied that whenever it was necessary to say that a sign changed, the Torah says that it changed. Regarding the nega of the hair and bead, however, the Torah only says that there isn’t any yellow hair in it. We infer from this that it causes impurity regardless of whether it came before the nega or after it.