Matthew 26:63

I adjure thee by the living God] Jesus consents to be put on His oath, thus declaring oaths before a magistrate to be lawful. The Christ, the Son of God] The high priest asks not merely whether He is the Messiah, but whether He is a divine Messiah. To claim to be the Messiah whom all good Israelites were expecting, was no crime, but to claim to be the Son of God, in the sense of God's equal, was blasphemy. Here the synoptists again strongly confirm the peculiar features of the Fourth Gospel, for how did the high priest know or suspect that Jesus claimed to be divine, unless Jesus had publicly said so at Jerusalem, as related in the Fourth Gospel? (John 5:17; John 8:56; John 10:33).