חָמֵשׁ מַעֲלוֹת עָשׂוּ חֲכָמִים בִּבְגָדִים וְאֵלּוּ הֵן. בִּגְדֵי עַם הָאָרֶץ מִדְרָס לְאוֹכְלֵי חֻלֵּיהֶן בְּטָהֳרָה וְכֵן עַמֵּי הָאָרֶץ עַצְמָן כְּזָבִין לְטָהֳרוֹת כְּמוֹ שֶׁבֵּאַרְנוּ. וּבִגְדֵי אוֹכְלֵי חֻלֵּיהֶן בְּטָהֳרָה מִדְרָס לְאוֹכְלֵי מַעֲשֵׂר שֵׁנִי אֲבָל אוֹכְלֵי חֻלֵּיהֶן בְּטָהֳרָה וְהֵן הַנִּקְרָאִים פְּרוּשִׁים אֵינָם כְּזָבִים אֲפִלּוּ לִתְרוּמָה הֲרֵי זֶה הַפָּרוּשׁ טָהוֹר אֲפִלּוּ אִם נָגַע בָּהּ בְּגוּפוֹ. וּבִגְדֵי אוֹכְלֵי מַעֲשֵׂר שֵׁנִי מִדְרָס לְאוֹכְלֵי תְּרוּמָה. וּבִגְדֵי אוֹכְלֵי תְּרוּמָה מִדְרָס לְקֹדֶשׁ אֲבָל אוֹכְלֵי תְּרוּמָה עַצְמָן אֵינָן כְּזָבִין בְּקֹדֶשׁ. וּבִגְדֵי אוֹכְלֵי קֹדֶשׁ מִדְרָס לְחַטָּאת כְּמוֹ שֶׁבֵּאַרְנוּ בְּהִלְכוֹת פָּרָה אֲדֻמָּה אֲבָל הַטָּהוֹר לְקֹדֶשׁ אֵינוֹ כְּזָב לְחַטָּאת:
Our Sages established five categories with regard to the ritual purity of clothes. They are the following: a) The clothes of an unlearned person are considered as a midras, an article on which a zav had been supported, for people who partake of ordinary food in a state of purity. Similarly, the unlearned people themselves are considered as zavvim with regard to pure substances, as we explained. b) The clothes of people who partake of ordinary food in a state of purity are considered as a midras for those who partake of the second tithe. The people who partake of ordinary food in a state of purity themselves - they are called perushim - are not considered as zavvim. Even with regard to terumah, a perush is considered pure, even if he touches terumah with his hands. c) The clothes of people who partake of the second tithe are considered as a midras for those who partake of terumah. d) The clothes of people who partake of terumah are considered as a midras for those who partake of consecrated food. The people who partake of terumah themselves are, however, not considered as zavvim with regard to consecrated articles. e) The clothes of those who partake of consecrated foods are considered as a midras with regard to the offering of the red heifer, as explained in Hilchot Parah Adumah. A person who is pure with regard to consecrated foods is not considered as a zav with regard to the offering of the red heifer.
