במשנה (ראש השנה כ”ו ע״א): כל השופרות כשרים חוץ משל פרה מפני שהוא קרן, אמר רבי יוסי והלא כל השופרות נקראו קרן שנאמר (יהושע ו, ה) במשך בקרן היוֹבל
We learn in the Mishnah that all horns (השופרות) except that of a cow (פרה) may be used to fulfill the commandment to sound the שופר on Rosh Hashanah, because the horn of a cow is called “קרן”. R. Jose disagrees because every שופר is called “קרן” as it is written “במשך בקרן היובל” (when they make a long blast with the ram’s horn).
The objection is raised in the Gemara: R. Jose was surely correct in his response to the opinion of the Rabbis. But the position of the Rabbis is that every שופר is called both “קרן” and “שופר”, while the horn of a cow is called only “קרן”, but not “שופר”.
This Mishnah can be understood aggadically by way of the Midrash Tanhuma on פרשת וירא.
[Abraham said to God after the עקידה] “I had an answer in my heart with which I could have answered You: ‘Yesterday, You told me (Genesis 21:12) “כי ביצחק יקרא לך זרע” (for through Isaac shall your descendants be named) and now You say to me (Genesis 22:2) “והעלהו שם לעלה” (bring him up there for a burnt offering).’ But I overcame my evil inclination, and I did not answer You. So, when the children of Isaac will transgress and find themselves in difficulty, may the עקידה be remembered for their sake, and may it be considered by You as if his ashes were piled on top of the altar, so that You may forgive them and save them from their trouble.”
The Holy One Blessed Be He answered him: “You said your piece. Now I will say mine. The children of Isaac will sin before me in the future, and I will judge them on Rosh Hashanah. But if they ask me to find some merit for their sake whereby to remember the עקידה of Isaac, let them sound the שופר of this ram before me.”
Abraham asked: “And what is a שופר?”
He said to him: “Look behind you.”
Immediately (Genesis 22:13) “Abraham raised his eyes and saw, and behold a ram was caught in a thistle by his horns.”
And our master explained this discussion by first considering the verse “And he saw, and behold a ram,” which is a great wonder. For the whole purpose of an animal sacrifice is that the one bringing the sacrifice, by offering the life of the animal in place of his own, should be inspired to repent. What purpose could have been served by offering the ram in place of Isaac? Abraham our father and Isaac his son had just been ready and willing with all their souls to perform the aqeidah, displaying in the fullest measure that holy feeling that can be achieved by a person only by offering a sacrifice. And, if we reflect, it would seem that through the aqeidah Abraham our father, purified and perfected the essence of his character and ingrained in his descendants till the end of time, to the degree that it became their inborn nature, to stand like a pillar of iron against those who would push them away from the belief in God. Thus, even the weak-minded among our people have not ceased to sacrifice their lives or to be burnt in the fire. Even women and children stretched out their necks for the sanctification of God’s name rather than renounce their faith. The aptitude for this holy feeling has been passed down from generation to generation, and its source is the עקידה.
However, the essential test of the עקידה was not the act of the עקידה itself, because Abraham our father had already been thrown into a fiery furnace, and the Torah did not even bother to tell of the greatness of his holiness in this incident. Rather, the wonder of his holiness and righteousness is shown by his not questioning the traits of the Blessed One even though he had grounds for questioning them and, indeed, for posing a mighty, truly unanswerable, contradiction. And this is an astonishing level of trust that cannot be implanted in the soul of a person except by the effort of performing very many good deeds and by staying free of any stain and blemish, as indeed, Abraham our father surely did. Although each and every child of Israel is obligated not to have any doubt that he would withstand the test of sacrificing his life in a time of need, one’s principal effort must be to sanctify himself each day of his life through his reverent service to God.
Now the discussion between Abraham and the Almighty can be properly understood. For Abraham wanted the Holy One Blessed Be He to forgive the coming generations because of their trait that stems from the act of the עקידה, their willingness to sacrifice their lives. The Eternal therefore answered him: “if they want me to find a merit for their sake, let them sound the שופר of this ram before me.” Abraham our father was astonished. “What is the שופר?” What is more elevated, and what merit is there that could be greater than the trait of willingness to sacrifice one’s own life? [Translator’s note: In other words, what is the significance of a mere ram’s horn compared to Abraham’s willingness, which he had just demonstrated, to sacrifice Isaac on God’s command?] The Holy One Blessed Be He answered him, “Look behind you.” By which He meant, “look at your constant good deeds from your infancy until today, by which you perfected yourself to become exactly like a sacrifice.” And then he saw, and behold a ram, just like a sacrifice, free from any blemish, in the category of “הקריבהו נא לפחתך.” It is only such a creature that is fit to be brought to the altar.
According to this, one can say that the word “קרן” refers to the being in itself and its power to perform action. This power appears to be the power ingrained in the heart of every child of Israel to sacrifice his life to sanctify the name of God. However, the word “שופר” refers to the constant good deeds, as if to say “beautify your deeds” (שפרו מעשיכם). A child of Israel must therefore seek to achieve both. And that is why the Rabbis say in the Mishnah with which we started (in accord with whom the halakha is decided) that we need both, קרן and שופר. And in this merit, may the transgressions of Israel be forgiven. (שביב אש)