http://en.wikipedia.org/wiki/AeonTemporal æonThis means the same thing as the word eon: an eternal frame of time, eternity.Quantitatively, eon refers to a period of time of 1,000,000,000 years. However, geologists refer to the period in which animals evolved into abundance as the Phanerozoic Eon, which only lasts 545 million years, to the present day.
Platonic æonsThe word æon was used by Plato to denote the eternal world of ideas, which he conceived was "behind" the perceived world, as demonstrated in his famous cave-allegory.
Gnostic æonsIn many Gnostic systems, the various emanations of the God, who is also known by such names as the One, the Monad, Aiwn teleos (The Perfect Æon), Bythos, Proarkh (Before the Beginning), H'Arkh (The Beginning), are called æons. This first being is also an æon and has an inner being within itself, known as Ennoea (Thought), Charis (Grace), or Sige (Silence). The split perfect being conceives the second æon, Nus (Mind), within itself. Along with the male Nus comes the female æon Veritas (Truth).
The æons often came in male/female pairs called syzygies, and were frequently numerous (20-30). Two of the most commonly listed æons were Jesus and Sophia. The æons constitute the pleroma, the "region of light". The lowest regions of the pleroma are closest to the darkness; that is, the physical world.
When an æon named Sophia emanates without her partner æon, the result is the Demiurge (or Ialdaboth), a creature that should never have come into existence. This creature does not belong to the pleroma, and the One emanates two savior æons, Christ and the Holy Spirit to save man from the Demiurge. Christ then took the form of the man, Jesus, in order to be able to teach man how to achieve gnosis; that is, return to the pleroma.