John 11:51

Τοῦτο δὲ ἀφʼ ἑαυτοῦ οὐκ εἶπεν … προεφήτευσεν. ἀφʼ ἑαυτοῦ, “at his own instigation,” is contrasted with “at the instigation of God” implied in ἐπροφήτευσεν [Kypke gives interesting examples of the use of ἀφʼ ἑαυτοῦ in classical writers]. “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 mouthpiece of the Divine oracle.” Plummer. Calvin calls him “bilingual,” and compares his unconscious service to that of Balaam. John sees that this unscrupulous diplomatist, who supposed that he was moving Jesus and the council and the Romans as so many pieces in his own game, was himself used as God's mouthpiece to predict the event which brought to a close his own and all other priesthood. In the irony of events he unconsciously used his high-priestly office to lead forward that one sacrifice which was for ever to take away sin and so make all further priestly office superfluous. He prophesied “that Jesus was to die for the nation, and not for the nation only, but that also the children of God who were scattered in various places should be gathered into one”. ὅτι is rendered “because” by Weiss and others. Jesus was to die ὑπὲρ τὸ ἔθνος although not in Caiaphas' sense; and His death had the wider object of bringing into one whole, of truer solidarity than the nation, all God's children wherever at present scattered. Cf. John 10:16; Ephesians 2:14. The expression τὰ τέκνα τοῦ Θεοῦ is used proleptically of the Gentiles who were destined to become God's children. So Euthymius. For the phrase συνάγειν εἰς ἕν Meyer refers to Plato, Phileb., 378, C, and Eurip., Orestes, 1640.