In Ephesians 2:2 there is a cryptic passage which has mystified modern readers: “Wherein in time past ye walked according to the course of this world (the Aion of this Cosmos: ton aiona tou kosmou toutou), according to the prince of the power of the air (archonta tes exousias tou aeros), the spirit (pneumatos) that now worketh in the children of disobedience…”
The word “air” or Aer (“aeros”) is described in terms of having dominion (archonta) and power (exousias). In Greek mythology Aer is one of the primeval deities, among the very first gods to come into existence. The very first deity is the goddess Khaos (Chaos) which means void or air. She is often identified with Aer, or Aer is a lower manifestation or descendent of her.
Regarding the Ephesians passage and its ancient context. It was written to Greek readers and reflects a proto-Gnostic worldview where pagan gods were transformed into archons, authorities, principalities and powers (Eph. 6:12). Aer is one of these powers and in this passage it may even be a reference to Khaos, as Khaos and Aer can be one and the same in ancient Greek thought. Moreover, if I’m correct in this then it may be that the term “Aion of this Cosmos”  may be a reference to Khaos, who among the Greeks was said to be the very first of all the gods.
The passage below is from the ancient poet & comedian Aristophanes which is dated back to the 4th century BC. Here we can see an example of Chaos and Aer being named among the earliest, primeval gods. The context here is that Chaos, Night, Darkness & Eros were the only gods that existed before Air, Earth & Heaven (Aer, Gaia & Ouranos):
“At the beginning there was only Chaos, Night, dark Erebus (Darkness), and deep tartarus (the dark pit: identified with Hell by pagans, Christians & Gnostics). Earth (Gaia), Air (Aer) and Heaven (Ouranos) had no existence. Firstly, blackwinged Night laid a germless egg in the bosom of the infinite deeps of Erebus, and from this, after the revolution of long ages, sprang the graceful Eros with his glittering golden wings, swift as the whirlwinds of the tempest. He mated in deep Tartarus with dark Chaos…” (Quoted from Aristophanes, Birds, 690f.)
Aristophanes’ theme that Earth, Heaven, Night and Darkness are primeval beings that have their origin from Chaos is surely based on the 7th century poet Hesiod and his Theogeny where Chaos is said to be the first of all the gods from whom came Earth, Eros, Darkness (Erebos) and Night (line 114ff.). 
And here again from Aristophanes, from his play Clouds. This is a prayer, placed in the mouth of Socrates, in which the boundless Aer is praised as a mighty king:
“Oh most mighty king, the boundless Aer, that keepest the earth suspended in space, thou bright Aether and ye venerable goddesses, the Clouds, who carry in your loins the thunder and the lightning, arise, ye sovereign powers and manifest yourselves in the celestial spheres to the eyes of your sage.” (Clouds, 262)
Another detail in Ephesians 2:2 is that Aer is connected with the “spirit” (pneumatos) that works in the “children of disobedience”. This may be understood to mean that the very air in the world exists in opposition to the ineffable, un-named Father above (Eph. 1:21). This very air that man breaths is itself an afflatus in opposition, belonging to the Aion of this Cosmos  and not the true God. The very air is a power that inspires dis-obedience in mankind, to inspire opposition to the spiritual order above. It is the power of Aer who in turn is under the dominion of the Aion of this Cosmos. The term “Aion of this Cosmos” could be reference to Chaos, the primeval originator, or it could be a reference to Khronos or Saturn, as the god of time, which is documented among the Greeks and Romans (viz. that Aion is another name for Khronos or Saturn).
To show the unorthodox cosmology of Ephesians I offer this quote from Ephesians 6:12 where we read that the “principalities and powers” are adversaries of wickedness that reside in the heavenly places (epouraniois).
“For we wrestle not against flesh and blood, but against principalities (archas), against powers (exousias), against the rulers of the darkness of this world (world-rulers of the darkness: kosmokratoras tou skotous toutou), against spiritual wickedness in high places (heavenly places: epouraniois).” (Eph. 6:12)
Clearly this passage refers to wicked spiritual powers in the heavens. This is a concept consistent with a Gnostic world-view. Whereas Christian orthodoxy teaches that Satan was cast from Heaven to Earth. The passages here and above indicate that Ephesians is based on a completely different paradigm and is consistent with Gnostic thought.
1] In ancient Greek and Hellenistic culture the word “aion” can be another name for a god. An aion can refer to a god, a realm, the world or cosmos, or an age. Moreover the term “Aion of this Cosmos” could be an alternate expression of Paul’s term “the god of this world” (ho theos tou aionos toutou) in 2 Cor. 4:4. Both of these expressions resemble Gnostic terminology. We may regard them as proto-Gnostic in that the Pauline letters most certainly did influence and inspire a later generation of classic Gnostic writers. The Pauline letters may be regarded as an example of an earlier proto-Gnostic stage where the foundation of Gnostic Christian thought was emerging in the mind of Paul and other writers (viz. that Ephesians was not from Paul himself, but a later follower and interpreter of his doctrine).
2] In the Nag Hammadi text On the Origin of the World the writer proposes to argue against the popular opinion that nothing existed before Chaos, viz. the opening passage.
Sources: theoi.com/Khaos, Khronos; perseus.tufts.edu/Aristophanes, Hesiod.
By Jim West. Copyright © August 11, revised Sept. 3, 2014.
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