Torah's da'as makes the world bear fruit

איתא בעצרת על פירות האילן.

It is taught that on Atzeres (Shavuos) [judgment is passed] on the fruits of the tree.

The Mishnah teaches that Shavuos is the time of judgment for the fruit of trees; the Sefas Emes will draw out the inner meaning of fruitfulness on this day.

הענין הוא שבחי' קבלת התורה. הי' הדעת שנכנס בעוה"ז להיות מוכנים לעשות פירות כי קודם שמקבלין דעת א"א להוליד תולדות.

The matter is that the aspect of receiving the Torah was the da'as that entered this world, making [things] ready to produce fruit — for before one receives da'as it is impossible to bring forth offspring.

Matan Torah introduced da'as into the world, and da'as is the prerequisite for true productivity. Without the knowledge granted by the Torah, nothing can bring forth genuine "fruit" — lasting spiritual results.

ומקודם הי' ב' אלפים תוהו וכ' לא תהו. בראה לשבת יצרה ועיקר הבריאה הי' שיתפשט לעשות תולדות כמ"ש אשר ברא אלקים לעשות.

And beforehand there were two thousand years of tohu (chaos), and it is written, "He did not create it for chaos; He formed it to be inhabited" — for the essence of creation was that it should spread forth and produce offspring, as it says, "which God created to do."

The pre-Torah era was "tohu," but Hashem did not create the world to remain barren chaos; its very purpose is to be settled and fruitful. "Asher bara Elokim la'asos" — created "to do/make" — implies an ongoing, generative continuation.

ובקבלת התורה נתקיים זאת לכן כ' וידבר כו' הדברים האלה לאמר. פי' שיתפשט כח המאמרות.

And with the receiving of the Torah this was fulfilled; therefore it is written, "And He spoke… these words, leimor (to say)." The explanation is that the power of the [Divine] utterances should spread forth.

The Torah fulfilled creation's purpose of fruitfulness. The word "leimor" — "to say [over further]" — signals that the power of Hashem's utterances is meant to extend and propagate outward, generating more.

וזה עיקר התורה שניתן לבנ"י כמ"ש חז"ל רצה הקב"ה לזכות את ישראל הרבה להם תורה ומצות ה' חפץ כו' יגדיל תורה ויאדיר

And this is the essence of the Torah given to Bnei Yisrael, as Chazal said: "The Holy One wished to grant merit to Yisrael, [therefore] He gave them abundant Torah and mitzvos," "Hashem desired… He will make the Torah great and glorious."

This generative quality is the heart of the Torah given to Yisrael — the abundance of Torah and mitzvos through which the Torah is continually "made great," echoing the teaching of the previous pieces.

שרצה להיות הזכות ע"י בנ"י שהם ימשיכו כח התורה לכל המעשים ע"י המצות.

For He wished the merit to come about through Bnei Yisrael, who would draw the power of the Torah into all deeds by means of the mitzvos.

Hashem's plan is that Yisrael be the agents who extend the Torah's power into every action through the mitzvos — this is how the world becomes "fruitful."

וזה נעשה ביום הזה לכן יש לכל אחיזה בזה היום

And this came about on this day; therefore everything has a "grasp" on this day.

Since the power to make all things fruitful entered the world on Shavuos, every created thing has a connection and a stake in this day.

לכן יש בו גם ביטול יצה"ר שכל הטבע ג"כ מבטל עצמו ביום הזה ע"י שהתורה היא קיום כל הברואים

Therefore there is on it also a nullification of the yetzer hara, for all of nature too nullifies itself on this day, since the Torah is the sustaining force of all creatures.

Because the Torah is the very life-source of all creation, on Shavuos even nature and the yetzer hara become subordinate and nullified before it — bittul reaches even the natural order.

לכן כתיב חמץ תאפינה כמ"ש בזוה"ק אמור.

Therefore it is written [regarding the Shtei HaLechem], "they shall be baked as chametz," as explained in the Zohar, parashas Emor.

Unlike most offerings, the two loaves of Shavuos are chametz — and the Zohar explains that on this day even chametz, normally symbolic of the yetzer hara, is permitted, because the yetzer is subdued and transformed by the power of the Torah.

ועיקר תולדותיהם של צדיקים מצות ומעשים טובים:

And the essential "offspring" of tzaddikim are mitzvos and good deeds.

The truest "fruit" produced through the da'as of the Torah are the mitzvos and ma'asim tovim of the righteous — Rashi's teaching that the real progeny of tzaddikim are their good deeds, the fitting culmination of a day that is about bearing fruit.

Summary: Shavuos is the day of judgment for fruit because receiving the Torah brought da'as into the world — the prerequisite for all genuine productivity. The pre-Torah era of "tohu" was never creation's purpose ("He formed it to be inhabited"); the Torah fulfilled the world's generative mission ("leimor" — the Divine utterances spreading forth). Through abundant Torah and mitzvos, Bnei Yisrael draw the Torah's power into every deed, so that on this day even nature and the yetzer hara nullify themselves before the Torah (hence the permitted chametz of the two loaves) — and the true "fruit" of tzaddikim are their mitzvos and good deeds.