Every religion is based on the fundamental belief that it is possible for coarse, common, vulgar humanity to be transformed through a mysterious, sacred process into something special, valuable, beautiful, and lasting. Thus, there is a spiritual tradition of ascribing not two, but three aspects to the process of uniting our inner opposites, including our masculine and feminine sides.  
For example, Christianity has the Father, Son, and Holy Spirit, and ancient matriarchal religions were based on the triple Goddess of Mother, Maiden and Crone.  In essence, the third element suggests the new entity that comes into being as a result of the hierosgamos, the Sacred Inner Marriage.
The addition of the third element recognizes the psyche’s potential to grow out of its dualistic state of “twoness” into a transcendent “threeness,” a more spiritually wise and conscious way of being.  It represents our capacity to survive our initiations so as to develop a new way of honoring the quiet inner spiritual voice (i.e. the Holy Spirit or Wise Old Man) or the confident knowing of our deep, intuitive feminine wisdom, (i.e. the Wise Old Woman or Crone).  This means that the individual has discovered the aspect of God that dwells within every archetype, and has learned to listen to it and act on it with strength and integrity in everyday life. 
The following passage written by Jungian analyst Robert Bosnak in his book, Dreaming With an Aids Patient, describes the mysterious process that leads to three-ness as it manifests in the life of an individual who is committed to inner work:
“I’m reminded…of the image of marriage in alchemy.  Alchemists imagined the fusion of different metals into an alloy, a new metal, as a divine marriage where the king and the queen dissolved together in a dark stream of images.  They were reconstituted as a new being, a man-woman, a hermaphrodite, partaking of both sun and moon, gold and silver, the ultimate alloy. 
“The process the alchemists describe shows marriage [here Bosnak is referring to the inner marriage] as an ever more intensified struggle of opposing forces held together in a painful paradox.  This warring love leads to dissolution, in which the opposing forces fall apart and get a chance to reconstitute in a new form. 
“At one point, when the marital struggle has reached a point of frenzy—when the full force of the joint family neurosis has hit like a bomb—all that remains is the sense of burned-outness and death.  From all this darkness a new capacity for relationship emerges, hardened like a metal that has been switched time and again back and forth between the fire and the ice-cold water.  No living happily ever after for the alchemists.”
In other words, our ego’s determination to resolve the conflict between our conscious personality and a considerably intensified shadow which lives in a world of darkness can lead us to the depths, not only of cold depression, but of our lifeless souls. This same intolerable conflict is the catalyst that pushes us to find a way in which the two can live together; and if we can tolerate the fiery tension that comes with this search, it will launch us onto the path toward spiritual wholeness. 
“As within, so without.”  This is the same process that can transform an outer-world couple relationship, the topic of my next post.
You can order my new book, Healing the Sacred Divide, at www.larsonpublications.com.