Sifra: 1. To teach us that the size of the Nega by a Michvah is a 'ki'Geris (like by a Nega on healthy skin); 2. To apply what is written by Se'eis ¹ to Baheres ² and vice-versa; 3. To apply what is written by Sh'chin to Michvah ³ and vice-versa.

Sifra: 1. To teach us that Michvah is not Metamei because of Michyah - not at the beginning, not at the end of the first week and not after he has been declared Tahor; 2. To preclude from the Din of Tum'ah where the Michvah spread into a Bohak (a Tahor plague on the skin) at the end of the first weeek or after he has been declared Tahor; 3. To preclude a fifth appearance (any appearance that is less than the four appearances specified earlier) from the Din of Nega'im.