Shavuos as Atzeres, the inner point of the festivals

וידבר משה את מועדי ה' כו'.

"And Moshe spoke the appointed times of Hashem…" (Vayikra 23:44).

The verse states that Moshe Rabbeinu conveyed the festivals to Bnei Yisrael, which Chazal expound further.

משה תיקן לישראל להיות שואלין ודורשין בענינו של יום כו'.

Moshe instituted for Yisrael that they should ask and expound concerning the matter of the day (Megillah 32a).

Moshe established that on each festival Bnei Yisrael study and discuss the themes of that very day.

פי' מו"ז ז"ל שנתן זה הכח והארת היו"ט לכל איש ישראל שיוכל לדרוש ולחקור בענינו של יום כו'.

My grandfather, of blessed memory, explained that he gave this power and the illumination of the Yom Tov to every Jew, that he should be able to expound and investigate the matter of the day.

His grandfather taught that Moshe transmitted the spiritual light of each festival to every individual Jew, empowering him to draw out its meaning.

וי"ל וידבר מלשון הנהגה שהנהיג הארת המועדות אל בנ"י.

And one can say that "vayedaber" (and he spoke) is from the language of leadership (hanhagah) — that he led the illumination of the festivals to Bnei Yisrael.

The word vayedaber connotes guiding or leading; Moshe channeled and directed the light of the moadim toward the people.

לכן צריך כל איש ישראל להתבונן בכל מועד להיות מוכן לקבל פני ה' כמ"ש יראה כל זכורך.

Therefore every Jew must contemplate on each festival in order to be prepared to receive the Presence of Hashem, as it is written, "all your males shall appear (yera'eh)" (Shemos 23:17).

Each festival calls for inner reflection so that one is ready to "appear before" and receive the face of Hashem.

ואף שעיקר המצוה אין לנו.

And even though the essential mitzvah (of appearing in the Bais Hamikdash) we do not have nowadays —

Without the Bais Hamikdash, the literal commandment of pilgrimage and appearing cannot be fulfilled.

מ"מ ההכנה בלב להעמיד עצמו לפני השי"ת הוא העיקר.

— nevertheless, the preparation in the heart to stand oneself before Hashem is the main thing.

The inner readiness of the heart to stand before Hashem is the essence of the festival, even in the absence of the Mikdash.

ובפרט ביום הזה שעמדנו לפני השי"ת בהר סיני ומצוה לזכור יום זה לעולם כמ"ש יום אשר עמדת לפני ה' אלקיך בחורב.

And especially on this day (Shavuos), when we stood before Hashem at Har Sinai, and it is a mitzvah to remember this day forever, as it is written, "the day on which you stood before Hashem your God at Chorev" (Devarim 4:10).

Shavuos commemorates standing before Hashem at Sinai — a day the Torah commands us never to forget.

פי' שבשעת מתן תורה נתדבקו נפשות בנ"י בהשי"ת כמ"ש נפשי יצאה כו' וכ' פנים בפנים דיבר ה' שנתגלה להם עיקר החיות של כל הבריאה בלי שום הסתר כמ"ש אנכי ה' אלקיך שהוא הכח של כל הנבראים.

The meaning is that at the time of Matan Torah the souls of Bnei Yisrael cleaved to Hashem, as it is written, "my soul departed" (Shir HaShirim 5:6), and it is written, "Face to face Hashem spoke" (Devarim 5:4) — that there was revealed to them the essential life-force of all creation without any concealment, as it is written, "I am Hashem your God" (Shemos 20:2), who is the power of all created beings.

At the giving of the Torah the souls of Bnei Yisrael clung to Hashem in total deveikus, and the inner life-force animating all creation was revealed openly in the words "I am Hashem your God."

לכן יכול כל אדם למצוא גילוי זו בכל שנה ביום זה וחג הזה הממוצע בין פסח וסוכות ומחבר אותם ונק' עצרת שהכל פונים אליו והוא הפנימי שבכולם:

Therefore every person can find this revelation each year on this day; and this festival, which stands in the middle between Pesach and Sukkos and joins them, is called Atzeres, for all turn toward it, and it is the innermost of them all.

That Sinai revelation can be recaptured every Shavuos; positioned between Pesach and Sukkos, Shavuos binds them together as Atzeres — the inner point to which all the festivals turn.

Summary: Moshe Rabbeinu transmitted the light of every festival to each individual Jew, so that even without the Bais Hamikdash the heart's preparation to stand before Hashem is the essence; on Shavuos especially one can recapture the Sinai revelation of deveikus and the open disclosure of "I am Hashem your God," for Shavuos is Atzeres, the innermost point uniting Pesach and Sukkos.