Jesus answered,
My kingdom is not of this world: if my kingdom were of this world, then would my servants fight, that I should not be delivered to the Jews: but now is my kingdom not from here.
All Commentaries on John 18:36 Go To John 18
Cyril of Alexandria
AD 444
He dispelled the fear Pilate felt as the appointed guardian of Caesar's kingdom, for he supposed that Christ was meditating insurrection against temporal rule, as the Jews had vainly talked. For they hinted at this when they said: If this Man were not an evildoer, we should not have delivered Him up unto thee; meaning insurrection by the evil they said He was doing. For they affected to be so well-disposed to the Romans, as not even to be able to utter the word revolt. For this cause, then, they said they had brought Him to Pilate, to suffer judgment. Christ, in His reply, denied not that He was a King, for He could not but speak truth; but He clearly proved that He was no enemy to Caesar's rule, signifying that His Kingdom was not an earthly kingdom, but that He reigned, as God, over heaven and earth, and yet greater things than these.
What proof, then, did He give? and how did He remove this suspicion? He says, that He had never employed any spearmen or warriors, and had never had with Him any men at all resolved on resistance; not merely in order to prevent His losing His Kingdom, but not even, that He might escape from the imminent danger cast upon Him by the hand of the Jews; for it did not proceed from their ruler himself, namely, Caesar. When, then, He had shown the groundlessness of this outcry by so clear a proof, Pilate perceived that the presumptuous attempt against Christ was without excuse. Yet, without any compulsion, and when there was nothing to incite him to that consequence, he complied with the pleasure of the Jews, to the perdition of his own soul, and shared with them the guilt of having put Christ to death. Christ, indeed, when He said that His Kingdom was a supernatural kingdom, not only freed Pilate from all alarm, and dispelled his suspicions about an insurrection, but induced him also to have an exalted opinion of Him, and by His reply in some sort commenced to instruct him.