Aion is the term used to describe the Christian age, which concludes with the Parousia of Christ and the emergence of the Antichrist. In "Aion," C.G. Jung explores the transformations of the psychological situation within the Christian aeon through an examination of Christian, Gnostic, and alchemical symbols of the Self. Central to all considerations is the attempt to clarify, amplify, and connect the archetype of the Self with the traditional figure of Christ. It is crucial to understand that Christ is viewed as a symbol of all-encompassing wholeness, embodying all characteristics of an archetype. Jung's psychological critique focuses on the theological doctrine of privatio boni, which posits that evil does not stand in opposition to good but rather signifies its diminishment. By excluding the evil power, Christ represents only one half of the archetype, while the other half appears in the Antichrist. A denial of the reality of evil as a conditional counterpart to good must lead to a metaphysical dualism, in which heaven and hell are separate and hostile opposing forces. The psychological aspects of human individuation must be examined in light of this Christian tradition, which has been inclined to deny the reality of evil. Not only experience but also a series of symbols throughout history argue against the exclusion of the evil power from the empirical Self. Through the examination of the symbol of the fish, which was early associated with Christ and also played a central role in astrology as a sign of opposition, Jung demonstrates that the repression of the dual aspect of good and evil has conjured the disastrous dualism that psychology seeks to overcome.