The motif of the hierosgamos, or mystic marriage of the opposites, is a familiar one in alchemical symbolism. It is often pictured as twin children - the brother-sister pair - embracing in the waters of the unconscious, as in figure 80. In this picture, the sacred temenos is not a garden as in our Tarot, but a sealed alchemical vessel which contains and protects the experience, preventing it from spilling out into overt life. That the hierosgamos is an inner happening rather than an outer sexual alliance is emphasized by its incestuous nature. Psychologically, incest symbolizes one's relationship to himself. It takes place within one's own psychic family, so to speak. [Image: Image] Fig. 80 Alchemical Twins in a Vessel Naturally such an inner experience of unity will transform the hero's relationships in the outside world also. If the hierosgamos is experienced and contained, he will emerge with a renewed sense of wholeness able to relate more consciously and creatively to his wife or lover. But if he projects the lost half of himself onto another human being, he remains forever incomplete.
— Sallie Nichols
The sealed vessel matters more than the union it contains. Alchemy did not draw the brother-sister pair embracing in open air, in a garden where anyone might walk through — it drew them inside glass, inside metal, inside something that holds. The temenos is not decoration; it is the condition under which the experience is actual rather than theatrical. What spills out becomes a storyline, a relationship, a search for the human being who will finally complete the one who remains incomplete. That search is older than romantic love; it is the soul's conviction that the missing half lives somewhere outside, that desire is spatial, that the longing for wholeness can be satisfied by proximity to another person.
It cannot. Not because other people are insufficient, but because the lost half is not elsewhere — it has been there, on the other side of a threshold inside, the whole time. The incest symbolism insists on this with a brutality that polite interpretation usually softens: what the soul wants, it already contains. The outer lover then becomes neither the destination nor the obstacle, but something more interesting — the figure in whom the inner marriage either finds its reflection or gets mistaken for its substitute. That distinction, between reflection and substitution, is the psychological work the vessel was built to make possible.
Sallie Nichols·Jung and Tarot: An Archetypal Journey·1980