Talmud for Parah 5:1
הַמֵּבִיא כְּלִי חֶרֶס לְחַטָּאת, טוֹבֵל וְלָן עַל הַכִּבְשָׁן. רַבִּי יְהוּדָה אוֹמֵר, אַף מִן הַבַּיִת הוּא מֵבִיא וְכָשֵׁר, שֶׁהַכֹּל נֶאֱמָנִים עַל הַחַטָּאת. וּבַתְּרוּמָה, פּוֹתֵחַ אֶת הַכִּבְשָׁן וְנוֹטֵל. רַבִּי שִׁמְעוֹן אוֹמֵר, מִן הַסֵּדֶר הַשֵּׁנִי. רַבִּי יוֹסֵי אוֹמֵר, מִן הַסֵּדֶר הַשְּׁלִישִׁי:
One who brings an earthenware vessel for the <i>chatat</i> [to fill with water to be sanctified by the ashes of the red heifer], he immerses himself [first, for purification], and sleeps at the furnace [in order to make sure no impure person touches it once it is completed]. Rabbi Yehuda says: He can even bring it from the house [of the potter] and it is valid, since [the testimony of] everyone believed regarding the <i>chatat</i> [due to the stringency of the matter]. And regarding <i>trumah</i> [a portion separated from grains and fruit grown in Israel and given to a priest, and which must be kept pure], one should open the furnace and take it [to ensure that the vessel stays pure]. Rabbi Shimon says: from the second row [and not from the first row, since someone impure may have already opened the furnace and touched it]. Rabbi Yose says: from the third row.