Milah binds to the Thirteen Attributes and teshuvah

לפרשת מילה אמרו חז"ל גדולה מילה שנכרתו עלי' י"ג בריתות.

Concerning the portion of milah (circumcision), Chazal said: Great is milah, for thirteen covenants were forged over it.

The mitzvah of bris milah is so weighty that the Torah uses the word "bris (covenant)" thirteen times in connection with it.

כי ברית הוא התקשרות ואיתא בגמ' ולדבקה בו הדבק במדותיו מה הוא רחום חנון כו'.

For a "bris" is a bond of attachment, and it is taught in the Gemara: "to cleave to Him" — cleave to His attributes; just as He is merciful and gracious, so too you.

A covenant means a binding connection; cleaving to Hashem means emulating His middos, being compassionate and gracious as He is.

א"כ הי"ג בריתות הם התדבקות בכל הי"ג מדות שלמעלה ובכח המילה יכולין לתקן כל המדות ויכולין בזה לעורר הי"ג מדות של רחמים בשמים וכמו בברית הלשון ע"י הזכרת י"ג מדות אין חוזרת ריקם והוא בבחי' דיבור כמו כן יש בחי' מעשה ע"י הצדיק שיש בו הי"ג מדות מעורר למעלה מדות הרחמים והוא בכח ברית מילה.

If so, the thirteen covenants are an attachment to all thirteen attributes above, and through the power of milah one can rectify all the middos, and thereby awaken the thirteen middos of rachamim (mercy) in Heaven. Just as with the "bris of the tongue" — through reciting the Thirteen Attributes the prayer does not return empty, and that is in the aspect of speech — so too there is an aspect of deed, through the tzaddik who possesses the thirteen middos, awakening the attributes of mercy above, and this is by the power of bris milah.

The thirteen "covenants" of milah bind a person to the Thirteen Divine Attributes of Mercy. As reciting the Yud-Gimmel Middos in prayer ("the bris of the tongue") never returns unanswered, so the act of milah — embodied in the tzaddik who carries those thirteen middos — arouses Hashem's mercy through deed rather than speech.

ואברהם אע"ה כתיב בו אחד הי' אברהם והוא בחי' הי"ג מדות שזה האחדות ודביקות בה' אחד באמת ובחי' י"ג מדות הוא בחי' התשובה.

And of Avraham Avinu it is written "Avraham was one," and this is the aspect of the thirteen middos, for this is the oneness and attachment to the one Hashem in truth; and the aspect of the thirteen middos is the aspect of teshuvah.

Avraham's "oneness" expresses his complete bond with the one Hashem, embodied in the thirteen attributes — and these attributes, being the channel of mercy, are the very root of teshuvah.

כי הנה העולם עומד על שבעת ימי הבנין.

For behold, the world stands upon the seven days of building.

The natural world is structured upon the seven days of creation — the seven lower middos.

והשבת הוא למעלה מזה ומושך הארה מג' ראשונות.

And Shabbos is above this, drawing illumination from the three "first ones."

Shabbos transcends the seven, drawing light from the three higher faculties (the first three sefiros) above the natural order.

אור שבעת הימים.

The light of the seven days.

Shabbos illuminates and elevates the light of all seven days of the week.

ומילה דוחה שבת שהוא מושך הארה מי"ג מדות ג' על עשרה.

And milah overrides Shabbos, for it draws illumination from the thirteen middos — three upon ten.

Milah pushes aside even Shabbos because it reaches a yet higher source: the thirteen attributes (the three highest added upon the ten), a light loftier than that of Shabbos.

ולכן מילה בשמיני שהיא בחי' התשובה.

Therefore milah is on the eighth day, which is the aspect of teshuvah.

The eighth, rising above the natural seven, corresponds to teshuvah — that which transcends the fixed order of nature.

ואיתא אם חביבה מילה למה לא נתנה לאדם הראשון.

And it is asked: if milah is so beloved, why was it not given to Adam HaRishon?

Chazal raise the question of why so precious a mitzvah was withheld from the first man.

והתירוץ ע"ז כי האלקים עשה את האדם ישר אך אחר החטא הראשון הוצרך להמשיך תיקון מלמעלה ביותר כדאיתא במקום שבעלי תשובה עומדין אין צדיקים יכולין לעמוד.

And the answer to this: "Elokim made man upright," but after the first sin it became necessary to draw down a rectification from above to an even greater degree, as it is taught: "In the place where ba'alei teshuvah stand, complete tzaddikim cannot stand."

Adam was created perfect and needed no such tikkun; only after his sin was a higher repair required. And that loftier rung, accessed through teshuvah, surpasses even the level of those who never fell — which is why milah belongs to this post-sin world.

ולפי שתיקן אברהם את החטא המשיך דרך חדש מלמעלה וע"ז דרשו החכמה תעוז לחכם יותר מעשרה שליטים א' הי' בעיר ולכן ניתן לו ברית מילה שנכרתו עלי' י"ג בריתות כנ"ל:

And because Avraham rectified the sin, he drew down a new path from above; and on this they expounded "Wisdom strengthens the wise more than ten rulers" — "one was in the city"; therefore he was given bris milah, over which thirteen covenants were forged, as above.

Avraham repaired Adam's sin and thereby opened a new channel of mercy from above — the wisdom that surpasses the "ten rulers" (the ten lower powers) by reaching the higher three. As the unique "one" in the world, Avraham merited the bris milah with its thirteen covenants drawn from the Thirteen Attributes.

Summary: The thirteen "covenants" of bris milah bind a person to the Thirteen Divine Attributes of Mercy, enabling him to rectify all his middos and awaken Hashem's rachamim — by deed (the tzaddik) as the recitation of the Thirteen Attributes does by speech. These attributes are the root of teshuvah, which transcends nature: Shabbos rises above the seven days of creation, and milah, on the eighth day, rises even higher, drawing from the thirteen attributes (three upon ten). Milah was withheld from the sinless Adam but given to Avraham, who repaired Adam's sin and opened this new, higher path of mercy from above.