Eternity stands among the most philosophically charged terms in the depth-psychology corpus, where it appears not merely as theological inheritance but as a live structural problem for consciousness, time, and the nature of the psyche’s deepest ground. The corpus registers three broad positions in productive tension. First, the Neoplatonic position, most fully articulated by Plotinus, treats eternity as the positive, self-identical life of the divine intellect — not an endless duration but the changeless totality of being from which Time descends as a restless image. Second, a phenomenological-existential counter-position, voiced by McGilchrist drawing on Heidegger, Merleau-Ponty, and Kierkegaard, resists hypostatizing eternity as a separate realm and relocates it within temporal experience itself: the ‘moment’ as ‘an atom of eternity,’ eternity as adverb rather than noun. Third, depth-psychological and comparative voices — von Franz, Campbell, Aurobindo — approach eternity as the archetype of the timeless dimension of psyche, the aeonic register that coexists with, but transcends, ordinary chronological sequence. Pascal and John of Damascus introduce the soteriological stakes: eternity as the inescapable ultimate to which every human life must orient. Nietzsche’s ecstatic invocation — ‘I love you, O Eternity!’ — introduces the affective and Dionysian dimension. Together these voices make eternity indispensable to any depth-psychological account of time, transcendence, and the Self.