Jesus therefore said to him, "Unless you see signs and wonders, you will in no way believe."
Signs and wonders ... is not a reference to two kinds of miracles, but rather to the two qualities in every miracle.  A wonder is something exciting, phenomenal, and extraordinary; but the same deed, viewed in the light shed upon the person of Jesus, is a sign of the Lord's deity.  If the nobleman had indeed been in Jerusalem and had witnessed Jesus' mighty wonders there, the rebuke would have reference to the weakness of his faith in the light of the evidence he had witnessed.  The rebuke, however, was so stated as to encourage the nobleman to believe more fully.