In a nutshell: Cosmotheism is about using reason to guide one’s moral compass.
“And let us now understand the present state of man, so that we can distinguish true reason from false reason. Let us employ true reason, so that it can guide us across the threshold of Divine Consciousness.
The difference between true reason and false reason is this: True reason seeks to guide man’s actions in accord with the immanent consciousness of the Whole, while false reason does not.
The man or woman of true reason seeks order in all things, and he shuns chaos. He is pleased by a harmonious relationship between all the elements of his life and the world. He rejects that which clashes and does not fit, that which is alien.
He is happy in the knowledge that what was true and good yesterday will be true and good tomorrow. Through order and harmony, he seeks true progress, but he shuns frivolous change, which destroys the harmony between the past and the future.
He loves truth, and he hates falsehood.
He loves beauty, and he hates ugliness.
He loves nobility in all things, and he hates baseness.”
The esoteric stuff is not my cup of tea but I find it quite intriguing. Hitler identified with many aspects of Cosmotheism.