Moshe's power lives on in Torah we toil in

בענין הלימוד בליל שבועות.

Concerning the learning on the night of Shavuos.

The piece addresses the custom of staying awake to learn Torah on Leil Shavuos.

דצריכין להכין עצמו לקבלת התורה כדאיתא התקן עצמך ללמוד תורה.

For one must prepare himself to receive the Torah, as it is taught, "Prepare yourself to learn Torah" (Avos 2:12).

The night-long learning is a hachanah (preparation), readying a person to receive the Torah anew on Shavuos.

ובשעת מתן תורה שהי' לנו משה רבינו ע"ה לסרסור וכתיב ויוצא משה כו' העם לקראת האלקים.

And at the time of Mattan Torah, when Moshe Rabbeinu, peace be upon him, was a "broker" (sarsur) for us, it is written, "And Moshe brought out the people toward Elokim" (Shemos 19:17).

At Sinai, Moshe served as the intermediary who brought Bnei Yisrael to meet Hashem and receive the Torah — he prepared them and led them out to greet the Shechinah.

ועתה נשאר כחו של מרע"ה בתורה דכ' תורה צוה כו' משה מורשה.

And now the power of Moshe Rabbeinu remains within the Torah, as it is written, "Moshe commanded us the Torah, an inheritance (morashah)…" (Devarim 33:4).

Moshe's spiritual koach did not vanish; it is embedded in the Torah itself and bequeathed to every Jew as an inheritance.

שבחי' משה עצמו ג"כ מורשה בתורה.

For the aspect of Moshe himself is also bequeathed (morashah) within the Torah.

Reading "morashah" as a hint, the Sefas Emes says that Moshe's very essence — not only the text he transmitted — is inherited within the Torah we learn.

ועל ידי יגיעה בתורה נמצא לנו כחו של מרע"ה ומקרב אותנו לאבינו שבשמים:

And through yegiah (toil) in the Torah, the power of Moshe Rabbeinu is found by us, and it draws us near to our Father in Heaven.

When a person labors in Torah, he taps into Moshe's koach still present within it; Moshe then continues his role as the "broker," bringing the learner close to Hashem just as he brought the people to Sinai.

Summary: The learning on Leil Shavuos is a preparation to receive the Torah, paralleling how Moshe, as the "broker" at Sinai, led Bnei Yisrael out to meet Hashem. Since Moshe's own spiritual power remains bequeathed within the Torah ("Moshe commanded us the Torah, a morashah"), one who toils in Torah draws upon that very koach of Moshe, which brings him near to his Father in Heaven.