What does John 18:34 mean?

Jesus has already decided to submit to the will of God (Matthew 26:42), which will include His unfair abuse and execution (Matthew 20:18–19; Luke 18:32). However, He will continue to make the situation clear, leaving His enemies no room for excuses. In this case, Christ subtly points out that Pilate has no reason to be speaking with Him. Had the Roman governor felt Jesus was a political threat, he would have arrested Jesus himself. This encounter is only happening because the religious leaders of Jerusalem are pressing to have Jesus killed (John 11:49–53). Pilate is not "saying" these things—discussing Jesus as the "king" of the Jews—as a result of his own concerns. He's responding to what others are claiming.

Pilate's answer (John 18:35) continues his pattern of dismissive arrogance towards Israel (John 18:30–31). He admits that the matter clearly looks like a squabble between Jewish religious figures (Matthew 27:18; Mark 15:10). John's account here is likely a summary, but the key points are clear. Pilate will press Jesus to see if His "kingship" is an immediate threat to Roman rule, realize it is not, and seek to have Him released (John 18:38).