Avraham's two avodos of unity

והנה אברהם אע"ה הי' בו ב' הענינים כי מקודם היה בכלל בני נח וקירב כל הברואים להשי"ת כפי היכולת כמאמר המדרש אחות לנו שאיחה כל באי עולם להשי"ת.

Now Avraham Avinu contained both of these aspects, for at first he was among the Bnei Noach and brought all of creation close to Hashem to the best of his ability, as the Midrash says on "we have a sister (achos)" — that he united (icheh) all who come into the world to Hashem.

Before he was set apart, Avraham worked within the universal framework of mankind, drawing every person closer to Hashem and binding the whole world together in His service.

והי' זה בחי' יחוד ה'.

And this was the aspect of the unity of Hashem (yichud Hashem).

This first avodah was about revealing the oneness of Hashem across all of creation, gathering the scattered world back to its single Source.

אח"כ אמר לו השי"ת לך לך פי' לבחי' המיוחדת לך שהיא אומה הישראלית המיוחדת לה' בכל המעשים והדקדוקים ע"י המצות והיא בחי' התורה שנקראת דרך כמ"ש חז"ל ע"פ אשר לא הלכו בה כו'.

Afterward Hashem said to him "Lech lecha (Go for yourself)" — meaning, to the aspect that is uniquely yours, which is the nation of Yisrael, set apart for Hashem in all its deeds and exacting details through the mitzvos; and this is the aspect of Torah, which is called a "way (derech)," as Chazal expound on the verse "in which they did not walk (halchu)."

The second stage was a more inward, particular mission: to form Bnei Yisrael, a nation devoted to Hashem through the precise practice of mitzvos, which is the path of Torah meant specifically for them.

ואמת שזה נוהג בכל איש ישראל כמאמר חז"ל מקודם יקבל עליו עמ"ש ואח"כ עול מצות.

And in truth this applies to every individual of Yisrael, as Chazal say: first a person accepts upon himself the yoke of Heaven (ol malchus Shomayim), and only afterward the yoke of the mitzvos.

Each Jew relives Avraham's two stages: first accepting Hashem's sovereignty in a general way, and only then taking on the detailed obligations of the mitzvos.

וכל מצוה צריך לעשות בהתבטלות לכלל ישראל כמו שאומרים בשם כל ישראל כמ"ש אשר קדשנו במצותיו.

And every mitzvah must be done with bittul (self-nullification) to the collective of Klal Yisrael, as we say in the name of all Yisrael, as it is written: "Who has sanctified us with His mitzvos."

A mitzvah is never a private act; one performs it as part of the whole nation, nullifying his individual self into Klal Yisrael — which is why the blessing speaks in the plural, "Who sanctified us."

וקבלת עומ"ש ויחוד ה' צריך להיות בכלל כל הבריאה לבקש שיתגלה כבודו ית' במהרה להיות ה' אחד ושמו אחד:

And the acceptance of the yoke of Heaven and the unity of Hashem must be on behalf of all of creation — to ask that His glory be revealed speedily, so that "Hashem will be One and His Name One."

Even the inward avodah of the individual Jew loops back to Avraham's first, universal mission: accepting Hashem's kingship not only for oneself but for the entire world, longing for the day His oneness is openly revealed.

Summary: Avraham embodied two avodos — first uniting all of creation under Hashem's oneness, then being singled out to father Bnei Yisrael, the nation devoted to Hashem through the detailed mitzvos. Every Jew relives this pattern: accepting Hashem's kingship before the mitzvos, performing each mitzvah in bittul to Klal Yisrael, and ultimately carrying that acceptance back outward to long for the revelation of Hashem's oneness over the whole world.