It's rather ironic that a discussion on what Christians believe would be based entirely on quotes from before the birth of Christ.

I think though that he did say something relevant to the question at hand: "The kingdom of God is inside you" (Luke 17:21) (ἡ βασιλεία τοῦ θεοῦ ἐντὸς ὑμῶν ἐστιν).

Now isn't God in his kingdom ?

Tat tvam asi.