The circle marks the boundary between the defined area within and the unquantifiable expanse without, between the measurable and the infinite, between the known and the unknowable. Indeed, the circle itself is a mystery, its value revealed only as the enigmatic π, which is not a number at all but a string of numbers that stretch on to fathomless infinity.
In the teachings of Kabbalah, the circle represents the encompassing light that frames our reality. Kabbalah differentiates between two types of divine light: a pervading inner light (ohr penimi), and a transcendent encompassing light (ohr makif).
Inner light describes a flow of divine energy that conforms to the parameters of our lives. The workings of nature, for example, or the processes of history, are in truth divine influences upon our existence; but these are divine influences that have assumed a form and nature that we can comprehend, relate to and internalize. The Torah, which is the divine wisdom and will made palpable to the human mind and implementable by human behavior, is another (albeit loftier) example of inner light.
But then there are the supra-natural, supra-rational manifestations of divine light. We call these miracles, existential mysteries, and mind-blowing experiences; we cannot understand them or assimilate them, only accept them and submit to them. This is not to say that the encompassing light is something that is outside of our being. In the words of the Tanya, it “penetrates our reality from head to foot, to its innerness and the inside of its innerness”: it is as basic (indeed, more basic) to our existence as the inner light. Yet, even as it suffuses our being, it remains aloof from us and beyond us, holding us in its embrace while eluding our attempts to grasp it and define it.
The soul of man, which was created in the image of G‑d, also emits both an inner and an encompassing light. It manifests itself via finite and definitive faculties, such as its senses, talents, intellect and feelings. But it also exhibits “encompassing” powers such as will, desire, faith, and the capacity for self-sacrifice. These are supra-rational and supra-natural powers which defy the constraints of physics and reason, and even the axioms of self-interest and self-preservation.
Marriage is the most supra-rational and supra-natural endeavor undertaken by man. For two individuals to become “one flesh” is to violate all the laws of ego and identity, to overcome the basic existential rule that one and one makes two. Thus, it is in marriage that we most emulate G‑d, creating life and eternalizing the temporal (by reproducing, man and woman create not only a child but also that child’s potential to have children, and for his children to have children, ad infinitum). When two become one, they transcend the finite and the mortal, unleashing the single human faculty that is infinite and divine.
Marriage thus requires the activation of the encompassing powers of all those involved. There are three partners to a marriage—man, woman and G‑d—and each party contributes the supra-existential dimension of its existence.
A marriage, therefore, consists of three circles: the feminine circle, the masculine circle and the divine circle. The wedding ceremony begins with the bride’s encircling of the groom. Seven times she walks around her husband-to-be, enveloping him in the encompassing light of her soul, committing herself to a bond that transcends reason and ego. The groom then does the same by encircling her finger with a ring, thereby consecrating her as his wife. And all this occurs under the chupah (wedding canopy), which represents G‑d’s embrace of the couple with His encompassing light, empowering them to transcend the confines of self and to unite in the eternal edifice of marriage.