Modernism fancied all spiritual powers a delusion. Nothing was real but matter in motion. The vast majority of contemporary Christians have adopted that worldview, with the exception of a whitelist of powers and miracles in which they feel obliged to believe in order to be Christian.
(As I’ve explored elsewhere, how many of those powers and miracles we feel obliged to believe depends to a large degree on how much academic credibility we aspire to.)
But this is not the teaching of Christianity. Christianity has always believed that the old gods are absolutely real—and that we are at war with them. Their heads are to be crushed; their images burned; their sacred groves cut down: Boniface had the right idea. Their followers are to be called to repentance, delivered from their willing slavery to the darkness into the freedom of the light.
On too many occasions over the past 2000 years, impatient Christians have tried to deliver the slaves by force, whether they wanted to be delivered or not. By now we have—let us hope—learned our lesson. The weapons of our warfare are most assuredly weapons, but they are not the carnal weapons of coercion. Our weapons are truth and righteousness, faith and salvation, readiness with the gospel of peace and the word of the Creator Himself, spoken afresh by us.
We live as invaders among the gods and their people. With word and water, bread, wine, and oil, we retake the territory unlawfully stolen from the Creator and prostituted to demons. Our ally is the whole creation that groans with birth pangs, waiting for the revelation of the sons of God.
Christianity is both relationship and religion. Without the relationship, the religion is empty. Without the religion, the relationship is confined to occasional experiences that, while beautiful in themselves, find no tangible expression in everyday life.
The relationship must be real. This is neither a thought experiment (“What if…?”), an arrangement of mental furniture (“I like to think of it like this”), nor a matter of observing principles (which would collapse relationship into religion). It is a real dealing with a particular Person (three, actually) outside ourselves. That means that we carry out our lives in the living presence of Almighty God. That Person births us into His new family, and thereafter grows us up as His children, with the goal of making us partakers of His divine nature. We engage in dialog; we ask for and receive help; we receive comfort and offer up praise. If we are not mystics in this sense, then we are not Christians; we are merely ideologues whose preferred genre is religion.
Now, with that said, what must the religion look like that gives tangible expression to such a relationship?
In order to function in this environment, we need a religious expression that…
- embraces the magical nature of the created, spoken world in which we live,
- addresses the spiritual realities of both human and angelic/demonic realms,
- integrates empirical knowledge of the fertile fields of natural revelation, and
- is concrete, livable, and permeates our daily lives.
So what does that look like? Well, that’s the project. I’m workin’ on it. Wanna join in?
Full Contact Christianity 
“… retake the territory unlawfully stolen from the Creator and prostituted to demons…”
Reading Michael Heiser’s The Unseen Realm on precisely this theme.
Good book. I’m a shade over halfway through it myself. The bit you quoted, by the way, is paraphrased from Augustin.