Most opinions agree that a Bris performed before the eighth day needs to be redone. The Kabalstic sages explain that the number seven corresponds to the natural cycle while the number eight reflects the supernatural, in the words of Kabala, “seven corresponds to the world while eight corresponds to beyond worldly”.
This means that the foreskin belongs and presents no issues within the worldly dimension, while in the super-worldly realm the foreskin is unacceptable. How? Generally that which is acceptable should always be acceptable at the very least on some level, while the unacceptable should essentially always be unaccepted.
In order to understand this paradox we must first delve into the significance of that which is worldly and that which is super-worldly. The world and everything in it is constantly imbued with spiritual energy, maintaining its existence and constant awareness of a deeper purpose, not only on a general level, but also every atom and smaller particles are maintained and cared for personally by the Almighty himself. Every occurrence in this world revolves around the specific role and course of every creature individually and collectively. In addition to guidance and enlivenment, everything in this world is also constantly created a new every moment, with every creature having an indispensible role in this abode. However as united as everything is in its common purpose, every creature still maintains individual identity on some level, separating itself from the rest of creation.
On the physical plane, coarse physical barriers of spatial differences separate us, and on the spiritual plane there is separation on a more refined level. While in the realm beyond the world and even beyond creation in general there is only one presence, the G-dly, everything else has no place and cannot exist as an individual identity.
Now we can understand why the foreskin can be acceptable on one level and unacceptable on another. The foreskin represents a barrier, a force of separation. Within the worldly context barriers are okay, but beyond that any barrier or separation in unacceptable and contradicts the inherent unified reality. In our lives it means that we may and must maintain and individual identity and presence, because otherwise the world cannot function. Yet at the same time we must know that the significance and the truth of our identities comes from a place where all of humanity is one, because it is specifically through this fusion that we make this world an abode for the Almighty.
We then realize that the truth is in the super-worldly perspective and our individualism is a reflection of our own arrogance. We aim for the reality of the eighth day, but we also realize that there is a seven before eight when it comes to our growth.
Rabbi Yehoshua Levin, Certified Mohel