"My kingship is not of this world". He then states, "if my kingship were of this world, my servants would fight that I might not be handed over to the Jews".This reasoning expressed an obvious truth, difficult to dispute. But in exactly what did this Kingdom, which was not of this world, consist? It was the Kingdom that Jesus had proclaimed throughout his preaching. During the trial, he summed up its essential content:
"You say that I am a king. For this I was born, and for this I have come into the world, to bear witness to the truth. Every one who is of the truth hears my voice". This declaration prompted a skeptical retort from Pilate: "What is truth?". However, as a fundamental piece of information about the Kingdom it requires those who read the Gospel to meditate on it. Christ is King since he bears witness to the truth. This witness entailed his supreme commitment in sacrifice. With the sacrifice of himself, Jesus established his Kingdom. He was born and lived on this earth with a view to this witness. He became King with the total gift of his love and of his life.
Link (here) to the full version of homily by Fr. Jean Galot, S.J., entitled , Jesus is King because he witnesses to Truth.