3. On the Kabalistic Tree of Life, one is the number of Kether, or Crown, the topmost sephirah. This is the first manifestation of the Divine that can be known. Above it is the lowest of the Three Veils of Negative Existence, the unknowable or transcendent Divine.
Uniting opposites and bringing them to unity, one, plays an important role in several forms of spirituality and magick. For example, basic sex magick can be described as 1+1=1 (one positive form of sexual energy, typically a "male" combined with one negative form of energy, typically a "female," produces one magickal result).