Yom Kippur coincides with the giving of the second tablets.

We can explain the connection between the two by noting that the repentance of Yom Kippur surpasses even “higher repentance” since it follows the “lower repentance” of the month of Elul and the days of selichot, and also the “higher repentance” of Rosh Hashanah and the Ten Days of Repentance. “Higher repentance,” as often explained, is the cleaving of the soul to its Divine source, not repentance for sin, and it corresponds to the verse “The spirit will return to G‑d Who gave it.”

It stems from the essence of the soul, the “yechidah,” which is “unity to unify You.”

This is the link between Yom Kippur and the Torah (the second tablets), for the Torah joins G‑d and Israel, so that they are “entirely one,” as expressed in the phrase “the one people to affirm Your Oneness.”

(Sichat Erev Yom Kippur 5747)