Now: Rosh Hashanah — Yom Teruah
The yovel is proclaimed with the shofarVayikra 25:9
First: which horn?
Any horn — but not a cow's?
Tanna KammaAny of them — except a cow's→ a cow's is a keren, not a shofar
Rabbi YossiA cow's horn too→ every shofar is called keren
“When they sound the keren hayovel”Yehoshua 6:5
A cow's horn grows in layers — a horn within a horn
“The accuser cannot be the defender”
the cow recalls the golden calf
Rosh Hashana 3:2
Which Horns Make a Kosher Shofar
כָּל הַשּׁוֹפָרוֹת כְּשֵׁרִין
כָּל הַשּׁוֹפָרוֹת כְּשֵׁרִין
חוּץ מִשֶּׁל פָּרָה,
מִפְּנֵי שֶׁהוּא קֶרֶן.
אָמַר רַבִּי יוֹסֵי,
וַהֲלֹא כָל הַשּׁוֹפָרוֹת נִקְרְאוּ קֶרֶן,
שֶׁנֶּאֱמַר (יהושע ו),
בִּמְשֹׁךְ בְּקֶרֶן הַיּוֹבֵל: