Consecrating man's gift of speech to Hashem on Rosh Hashanah

בר"ה נברא אדם.

On Rosh Hashanah, Adam (man) was created.

The Sefas Emes opens with the teaching that the creation of the first man took place on Rosh Hashanah, making the day fundamentally about the essence of the human being.

ועיקר מעלת האדם שהוא מדבר.

And the primary distinction of man is that he is a speaking being (medaber).

What sets man apart from all other creatures is the faculty of speech — he is the medaber, the one endowed with articulate language.

ולכן בתחלה צריכין לשעבד הקול והדיבור לשמים.

Therefore, at the outset, one must subjugate the voice and speech to Heaven.

Since speech is man's defining gift, the avodah of Rosh Hashanah begins with dedicating one's voice and speech entirely to the service of Hashem.

והוא קול שופר.

And this is the sound of the shofar.

The shofar's blast is the wordless "voice" offered up to Hashem — the raw kol (sound) dedicated to Heaven before it is even formed into words.

ופסוקי מלכיות זכרונות שופרות.

And the verses of Malchuyos, Zichronos, and Shofros.

Following the raw sound of the shofar, the articulate speech is consecrated through the recitation of the three sets of verses — Kingship, Remembrance, and Shofar — in which man's power of speech is turned toward Hashem.

כענין שכתבו חז"ל כשתינוק מתחיל לדבר אביו מלמדו תורה כו':

This is like what Chazal wrote: when a child begins to speak, his father teaches him Torah.

Just as a father directs his child's very first words toward Torah, so on Rosh Hashanah — the "birthday" of man as a speaking being — we consecrate the renewed gift of speech to Hashem from its very first use, through the shofar and the sacred verses.

Summary: Since man was created on Rosh Hashanah and his defining greatness is the power of speech, the day's avodah is to subjugate one's voice and speech to Heaven — first through the wordless sound of the shofar, then through the articulate verses of Malchuyos, Zichronos, and Shofros — just as a father directs a child's very first words toward Torah.