John 18:34 - Ellicott's Commentary On The Whole Bible

Sayest thou this thing of thyself, or did others tell it thee of me? — The most probable interpretation of the question is that which regards it as establishing a distinction between the title “King of the Jews” as spoken by Pilate and the same title as spoken by Jesus. In the political sense in which Pilate would use it, and in this sense only the claim could be brought against Him in Roman law, He was not King of the Jews. In the theocratic sense in which a Jew would use that title, He was King of the Jews.