John 11:51

not of himself Like Saul, Caiaphas is a prophet in spite of himself.

being high priest None but a Jew would be likely to know of the old Jewish belief that the high-priest by means of the Urim and Thummim was the mouth-piece of the Divine oracle. The Urim and Thummim had been lost, and the high-priest's office had been shorn of much of its glory, but the remembrance of his prophetical gift did not become quite extinct (Hosea 3:4); and -in that fatal year" S. John might well believe that the gift would be restored.