Halakhah for Parah 1:1
רַבִּי אֱלִיעֶזֶר אוֹמֵר, עֶגְלָה, בַּת שְׁנָתָהּ. וּפָרָה, בַּת שְׁתַּיִם. וַחֲכָמִים אוֹמְרִים, עֶגְלָה, בַּת שְׁתַּיִם. וּפָרָה, בַּת שָׁלשׁ אוֹ בַת אַרְבַּע. רַבִּי מֵאִיר אוֹמֵר, אַף בַּת חָמֵשׁ. כְּשֵׁרָה הַזְּקֵנָה, אֶלָּא שֶׁאֵין מַמְתִּינִין לָהּ, שֶׁמָּא תַשְׁחִיר, שֶׁלֹּא תִפָּסֵל. אָמַר רַבִּי יְהוֹשֻׁעַ, לֹא שָׁמַעְתִּי אֶלָּא שְׁלָשִׁית. אָמְרוּ לוֹ, מַה הַלָּשׁוֹן שְׁלָשִׁית. אָמַר לָהֶם, כָּךְ שָׁמַעְתִּי סְתָם. אָמַר בֶּן עַזַּאי, אֲנִי אֲפָרֵשׁ. אִם אוֹמֵר אַתָּה, שְׁלִישִׁית, לַאֲחֵרוֹת בְּמִנְיָן. וּכְשֶׁאַתָּה אוֹמֵר, שְׁלָשִׁית, בַּת שָׁלשׁ שָׁנִים. כַּיּוֹצֵא בוֹ אָמְרוּ, כֶּרֶם רְבָעִי. אָמְרוּ לוֹ, מַה הַלָּשׁוֹן רְבָעִי. אָמַר לָהֶם, כָּךְ שָׁמַעְתִּי סְתָם. אָמַר בֶּן עַזַּאי, אֲנִי אֲפָרֵשׁ. אִם אוֹמֵר אַתָּה, רְבִיעִי, לַאֲחֵרִים בְּמִנְיָן. וּכְשֶׁאַתָּה אוֹמֵר, רְבָעִי, בֶּן אַרְבַּע שָׁנִים. כַּיּוֹצֵא בוֹ אָמְרוּ, הָאוֹכֵל בְּבַיִת הַמְנֻגָּע פְּרָס, מִשָּׁלשׁ לְקָב. אָמְרוּ לוֹ, אֱמֹר מִשְּׁמֹנֶה עֶשְׂרֵה לִסְאָה. אָמַר לָהֶם, כָּךְ שָׁמַעְתִּי סְתָם. אָמַר בֶּן עַזַּאי, אֲנִי אֲפָרֵשׁ. אִם אוֹמֵר אַתָּה מִשָּׁלשׁ לְקָב, אֵין בּוֹ חַלָּה. וּכְשֶׁאַתָּה אוֹמֵר, מִשְּׁמֹנֶה עֶשְׂרֵה לִסְאָה, מִעֲטַתּוּ חַלָּתוֹ:
Rabbi Eliezer says: A calf [as referred to in the Torah] is a year old, and a cow is two years old. And the Sages say: a calf is two year old, and a cow is three or four. Rabbi Meir says: Even a five year old, an elderly one, is valid [for use in the purification ritual of the red heifer] but we don't wait for it [to age] lest it develop black hairs, so it does not become invalid. Rabbi Yehoshua says: I have only heard about a <i>shelashit</i> [i.e. three years old]. They said to him: What is the meaning of the language <i>shelashit</i>? He said to them: So I heard it, unelaborated. Ben Azzai said: I shall explain. If the language was <i>shelishit</i> [literally: third], then [it means] the third in number [i.e. the third calf born]; but since the language was <i>shelashit</i>, then [it means] three years old. They spoke similarly regarding a <i>rivaii</i> vineyard [a vineyard in its fourth year whose fruits are sanctified]. They said to him: What is the language of <i>rivaii</i>? He said to them: So I heard it, unelaborated. Ben Azzai said: I shall explain. If the language was <i>rivaii</i> [literally: fourth], then [it means] the fourth relative to others in number [i.e. the fourth vineyard which a man owns]; but since the language is <i>rivaii</i>, then [it means] four years old. Similarly they said: One [becomes impure] if he eats in a blighted house half a loaf, when there are three [loaves] to a kav [a certain volume of flour]. They said to him: [Instead] say 'when there are eighteen [loaves] to a se'ah'! [note: six kavs are equal to a se'ah.] He said to them: So I heard it, unelaborated. Ben Azzai said: I shall explain. If you say 'when there are three [loaves] to a kav,' that is without its challah [having been separated; challah is a portion of dough which must be removed from breads and given to a priest, but a loaf that small would not be obligated in challah]. But when you say 'when there are eighteen [loaves] to a se'ah', that is with its challah deducted.