Thanks for trying to answer it.
"What is above" would be the "heavenly" because it's above, ie. spiritual, holy, divine.
What is "below would mean either what's on earth below heaven or else whats in hell, below.
When it says "everything is above" it sounds like it means everything that exists is in the heavenly sphere.
"The imagination of those that are without knowledge" would be the imagining or illusion of those who lack the Christian "gnosis".
It reminds me of the idea in Advaita Hinduism
that the "absolute reality" is Brahman, the creative "Nature", whereas the world is Maya, illusion. In Hinduism, a key goal is to escape the material "illusory" world.
Reality - Any entity which is finite, temporal or can be defined using attributes is treated as unreal and the spirit (aatman) is supposed to be the only real entity. The spirit is attribute-less and infinite by definition. Any entity outside the realm of the spirit is Maya (unreal, finite, temporal and illusory).
In Adwaita, emphasis is laid on transcendental God as pure consciousness. It has more to do with the subjective nature of God. All that is objective i.e the creation is discarded as Maya or as an illusion, in spite of the fact that Maya also owes its existence to brahman.
God is,…..we must remember…. the creator and is’ the TOTAL universe i.e. all the good and even the bad have to depend on him for its existence.. Only he can let bad be created and only he can dissolve it. …….So, Bad and Sin, is just an illusion in our minds and god is beyond it (nirgun)…….. He perhaps lets bad exist in the gross world of maya (Hindu\Buddhist word for illusion that this entire universe is), for us to be punished by the bad, we create by our own wrong choices and actions http://www.esamskriti.com/essay-chapters/Reinterpreting-Dwaita-versus-Adwaita-1.aspx
Advaita Hinduism can be either pantheistic or AFAIK atheistic. Eastern Orthodox Christianity, on the other hand is definitely not pantheistic - God and His Creation are both real and separate.
The opposite of Advaita philosophy is Dvaita
philosophy in Hinduism, which is non-pantheistic theism.
According to the ESamskriti page, the famous Dvaita Hindu teacher, Madhva, rejected Advaitism and its theory of Maya, and instead proposed that God and the Creation were two separate real entities:
The scheme of five-fold difference spelled out by Madhva implies that this diversity of the world, perceived by our senses, is not an illusion or magic or Maya. Madhva is never tired of quoting numerous statements from scriptures, confirming the creation, preservation, regulation and control of the world of matter and souls by a Supreme Divinity. http://www.esamskriti.com/essay-chapters/Reinterpreting-Dwaita-versus-Adwaita-1.aspx
The theory of māyā was developed by the ninth-century Advaita Hindu philosopher Adi Shankara. However, competing theistic Dvaita scholars contested Shankara's theory, and stated that Shankara did not offer a theory of the relationship between Brahman and Māyā.
Another writer says:
According to Dvaita philosophy souls are eternal and are not created by God, yet, like maya or other fundamental realities they are not independent but are dependent on the Supreme God for their existence. Souls are many and uncountable. How come the individual souls which are mingled with Maya (māyān + veshtita = mayanveshtita, meaning, enveloped or completely covered with maya) can be of the same level of the Supreme God which is ever transcendental to maya and also to whom maya even cannot touch. Maya, though revocably but strongly, binds the souls but cannot bind God, it cannot even touch God. http://www.justforkidsonly.com/truth/?cat=813
See also the relationship between avidya (ignorance) and maya (illusion)
In Hinduism, Avidya includes confusing the mundane reality to be the only reality, and it as a permanent though it is ever changing. Its doctrines assert that there is a spiritual reality consisting of Atman-Brahman, one that is the true, eternal, imperishable reality beyond time.https://en.wikipedia.org/wiki/Avidya_(Hinduism
The effect of avidya is to suppress the real nature of things and present something else in its place. In effect it is not different from Maya (pronounced Māyā) or illusion. Avidya relates to the individual Self (Ātman), while Maya is an adjunct of the cosmic Self (Brahman).