The following is an excerpt from The MacArthur New Testament Commentary on John 18.

Pilate answered, “I am not a Jew, am I? Your own nation and the chief priests delivered You to me; what have You done?” Jesus answered, “My kingdom is not of this world. If My kingdom were of this world, then My servants would be fighting so that I would not be handed over to the Jews; but as it is, My kingdom is not of this realm.” (John 18:35-36)

Since it was now clear that Pilate was merely repeating the charge of the Jewish leaders, Jesus answered his question. He was a king, but not a political ruler intent on challenging Rome’s rule. “My kingdom is not of (Greek ek; “out from the midst of”) this world,” He declared. Its source was not the world system, nor did Jesus derive His authority from any human source. As noted earlier, He had rejected the crowd’s attempt to crown Him king. He also passed up an opportunity to proclaim Himself king at the triumphal entry, when He rode into Jerusalem at the head of tens of thousands of frenzied hopefuls.

To reinforce His point, Jesus noted that if His kingdom were of this world, then His servants would be fighting so that He would not be handed over to the Jews. No earthly king would have allowed himself to have been captured so easily. But when one of His followers (Peter) attempted to defend Him, Jesus rebuked him. The messianic kingdom does not originate from human effort, but through the Son of Man’s conquering of sin in the lives of those who belong to His spiritual kingdom.

Christ’s kingdom is spiritually active in the world today, and one day He will return to physically reign on the earth in millennial glory (Rev. 11:15; 20:6). But until then His Kingdom exists in the hearts of believers, where He is undisputed King and sovereign Lord. He was absolutely no threat either to the national identity of Israel, or to the political and military identity of Rome.

That the Lord spoke of being handed over to the Jews is significant. Far from leading them in a revolt against Rome, Jesus spoke of the Jews (especially the leaders) as His enemies. He was a king, but since He disavowed the use of force and fighting, He was clearly no threat to Rome’s interests. The Lord’s statement rendered the Jews’ charge that He was a revolutionary bent on overthrowing Rome absurd.