And when he was demanded by the Pharisees, when the kingdom of God should come, he answered them and said,
The kingdom of God comes not with outward observation:
All Commentaries on Luke 17:20 Go To Luke 17
John Cassian
AD 435
If the devil has been driven out and sin no longer reigns, then the kingdom of God is established in us. As it is written in the Gospel, “The kingdom of God does not come with observation, nor will they say, ‘Lo here,’ or ‘Lo, there.’ Truly I say to you that the kingdom of God is within you.” The only thing that can be “within us” is knowledge or ignorance of the truth and the affection for righteousness or sin by which we prepare our hearts to be a kingdom of Christ or the devil. St. Paul described the nature of this kingdom in this way: “For the kingdom of God is not food and drink, but righteousness and peace and joy in the Holy Spirit.” If the kingdom of God is within us and is righteousness, peace and joy, then someone that remains in these is surely within the kingdom of God. Someone that remains in unrighteousness, conflict and the melancholy that kills the life of the spirit is already a citizen of the devil’s kingdom, of hell and of death. These are the signs whether it is God’s kingdom or the devil’s.