Imagine a far-off kingdom, ruled by a tyrannical dictator. He stole the throne while the rightful king was away, and he’s terrified the people are going to rise up against him. This dictator executes everyone who speaks against him, seizing their property and assets. 
Imagine the real king shows up in disguise, like Robin Hood sneaking into Prince John’s castle. The king looks like a beggar. But his people know him. And he works quietly in the shadows, garnering support, preparing them for a revolution. The seeds of the revolution are sown quickly, but quietly. 
In their secret meetings, the rebels refer to their proper ruler as The King, even though he has not yet regained his throne. In public, the rebels go about living their everyday lives under the thumb of the dictator, but secretly everything they do is working to subvert the fraud and replace him with the true king. 
The King promises to rid his people of the tyrant and invites them to be his co-regents, ruling the kingdom at his side. The rebels come to understand they won’t simply be ruled; they will rule alongside their master. Their anticipation quickly turns to excitement as they gather together, communicate with one another, and imagine what life will be like in the future kingdom. But, for the moment, the reality consists more in subversion than in authority. Right now, they focus their efforts on thwarting the dictator’s purposes, so more and more people come to understand he’s not worth following. 
All the language in the New Testament concerning Jesus’ kingship presents him as a king in disguise. In the gospels, it’s clear Satan has some measure of authority over the world, but he’s a fraud. Satan has absconded the throne God intended for men. The story of Jesus’ sacrificial death and subsequent resurrection is the story of God stealing it back. Ultimately Satan will be routed from the earth completely, and things will once again be the way God intended. 
But for the moment, we find ourselves living in contested territory.