They went not into the palace themselves, lest they should be defiled — By going into a house which was not purged from leaven, Deuteronomy 16:4. Matthew 27:2; Mark 15:1; Luke 23:1.
Related Commentaries of John 18:28
John 18:28
28 Then led they Jesus from Caiaphas unto the hall of judgment: and it was early; and they themselves went not into the judgment hall, lest they should be defiled; but that they might eat the passover.