Jesus answered them, "Destroy this temple, and in three days I will raise it up."
This verse shows that Jesus fully knew the consequences of casting out the money-changers; and, by this prophecy, he clearly foretold that they would indeed put him to death and that he would rise from the dead on the third day.  This statement made in response to the demand for a sign is similar in the Lord's answer to the demand of the Pharisees recorded in  Matthew 12:38ff.  In both instances, the only sign the Pharisees were promised was the Lord's own death, burial, and resurrection; but here he used the analogy of the destroyed temple raised again in three days, while there the "sign of the prophet Jonah" had exactly the same meaning!