א֣וֹ נֶ֗פֶשׁ אֲשֶׁ֣ר תִּגַּע֮ בְּכָל־דָּבָ֣ר טָמֵא֒ אוֹ֩ בְנִבְלַ֨ת חַיָּ֜ה טְמֵאָ֗ה א֤וֹ בְּנִבְלַת֙ בְּהֵמָ֣ה טְמֵאָ֔ה א֕וֹ בְּנִבְלַ֖ת שֶׁ֣רֶץ טָמֵ֑א וְנֶעְלַ֣ם מִמֶּ֔נּוּ וְה֥וּא טָמֵ֖א וְאָשֵֽׁם׃
Ou quando uma pessoa tocar em qualquer coisa impura, seja um cadáver de animal impuro, ou um cadáver de gado impuro, ou um réptil impuro, mesmo que isso lhe tenha passado despercebido, ele ficará impuro e será culpado.
Mishnah Shevuot
Oaths are of two kinds, subdivided into four; The laws concerning the discovery of having contracted uncleanness are of two kinds, subdivided into four; The laws concerning carrying on the Sabbath are of two kinds, subdivided into four. The symptoms of negas are of two kinds, subdivided into four.
Mishnah Kelim
The area within the wall [of Jerusalem] is holier, for it is there that lesser holy things and second tithe may be eaten. The Temple Mount is holier, for zavim, zavot, menstruants and women after childbirth may not enter it. The chel is holier, for neither non-Jews nor one who contracted corpse impurity may enter it. The court of women is holier, for a tevul yom may not enter it, though he is not obligated a hatat for doing so. The court of the Israelites is holier, for a man who has not yet offered his obligatory sacrifices may not enter it, and if he enters he is liable for a hatat. The court of the priests is holier, for Israelites may not enter it except when they are required to do so: for laying on of the hands, slaying or waving.
Mishnah Shevuot
The laws concerning the discovery of having contracted uncleanness are of two kinds, subdivided into four;[If] he became impure and was aware of it, then he forgot that he had been impure, though he remembered that the food was holy; [If the fact that it was] holy food was unknown to him, though he remembered that he was impure; [If] both were unknown to him; And he ate holy food, and was not aware, and after he had eaten, he became aware: in these cases he brings a sliding scale sacrifice. [[If] he became impure and was aware of it, then he forgot that he had been impure, though he remembered that [he was entering] the Temple; [If the fact that he was entering] the Temple was unknown to him, though he remembered that he was impure; [If] both were hidden from him; And he entered the Temple and was not aware, and after he had gone out, became aware: in these cases he brings a sliding scale sacrifice.