It can be said that a Temple is most appropriate (i.e. Truthful) when considered as a center of communication and exchange between the gene pools of the various Spiritual Traditions.  A Temple which is anything other than a True Center (of Universality and Synthesis) - anything other than the Quest for equilibrium, neutralization, and/or unification of differences and discrepancies - only pretends a basis in Spirituality.

The Great Arcanum is the Science and Art of Awakening the Consciousness.  It is that which takes the common Human into the realm of the Gods.