In the esoteric philosophy of Thelema, founded by Aleister Crowley in the early 20th century, an Aeon is a period of time defined by distinct spiritual and cultural characteristics, each accompanied by its own forms of magical and religious expression.
[1] Thelemites believe that the history of humanity is divided into a series of these Aeons, each governed by a particular deity or archetype that embodies the spiritual formula of the era.
The transition between these Aeons is understood not merely as a change in religious or cultural practices, but as a profound shift in the underlying spiritual paradigm that governs human existence.
The female aspect of the Godhead was revered due to a mostly matriarchal society and the idea that "Mother Earth" nourished, clothed and housed man closed in the womb of Matrix.
Crowley says of this Aeon in his Heart of the Master: Formula of Osiris, whose word is IAO; so that men worshiped Man, thinking him subject to Death, and his victory dependent upon Resurrection.
This aeon emphasizes self-realization, individualism, and the pursuit of one's True Will, symbolized by the child god Horus representing new beginnings and potential growth.
[8] Key figures such as Israel Regardie and Kenneth Grant highlight the transformative nature of this aeon, encouraging individuals to embrace their True Will and move beyond previous constraints.
We learn that Horus will be in his turn succeeded by Thmaist, the Double-Wanded One; she who shall bring the candidates to full initiation, and though we know little of her peculiar characteristics, we know at least that her name is justice.