18 So the Jews said to him, "What sign do you show us for doing these things?" 19 Jesus answered them, "Destroy this temple, and in three days I will raise it up." 20 The Jews then said, "It has taken forty-six years to build this temple, and will you raise it up in three days?" 21 But he was speaking about the temple of his body. 22 When therefore he was raised from the dead, his disciples remembered that he had said this, and they believed the Scripture and the word that Jesus had spoken.
One of the dominant Biblical images is of the Temple. Jerusalem was a city on a hill, and the Temple was on a mount within that city. It could be seen from miles away. Jerusalem was seen as THE place of worship for all Jews. They traveled to Jerusalem from far and wide on pilgrimage. There were at least two versions of the temple, as the first was destroyed by marauding invaders under Nebuchadnezzar. To build this incredible artifice took roughly seven years of labor by thousands of Israelites. Jesus says He alone will rebuild it in three days...what do you think He was trying to say here? What would you imagine the reaction of the Jews to be who knew the history of the original Temple?