Luna stands as one of the most densely layered symbols in the depth-psychological corpus, operating simultaneously as an alchemical principle, an archetypal figure, and a mode of consciousness. In Jung’s Mysterium Coniunctionis, Luna appears as the indispensable polar opposite of Sol: cold, moist, receptive, and feminine where Sol is hot, dry, active, and masculine. As the ‘universal receptacle of all things’ and the ‘first gateway of heaven,’ she gathers the powers of all the stars as in a womb, bestowing them upon sublunary creatures—a cosmological function that maps directly onto the anima’s role as mediator between collective archetypes and personal experience. The Church as Ecclesia-Luna enacts this same logic historically: her kenosis mirrors Christ’s, her darkening at the new moon enacting a ritual emptying into the solar principle. Abraham’s alchemical lexicon anchors Luna firmly in the opus: she is the white queen, bride of Sol, the albedo’s culmination, and mother of the philosopher’s stone. Moore’s reading of Ficino extends this into a living psychology of rhythm and embodiment, wherein Luna governs propitious timing, seasonal attunement, and the translation of archetypal fantasy into bodily, individual life. Greene and Sasportas transpose the symbol into astrological psychology, connecting the Moon’s phases to cycles of psychological fullness and decay. Across these voices, a central tension persists: Luna is at once illuminating guide and source of lunacy, purity and dangerous volatility.