They are two invisible spiritual kingdoms that are at war with one another. They are the kingdom of God and the kingdom of satan.
As a citizen of the kingdom of God through faith in Christ, you are automatically at war with the kingdom of Satan. You need to recognize this reality, become spiritually equipped, and learn how to fight against Satan’s kingdom.
Ephesians 6 vs 12
For we do not wrestle against flesh and blood, but against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places.
Books by Derek Prince