John 2:19

Jesus answered them, “Destroy this temple, and I will raise it again in three days.”

Jesus usually refused to give a sign to those who requested one, or He would point to His coming resurrection as the only sign they would get. Here, He gives the sign of his resurrection, but said in a parable (Matt 13:13-14). This He did to those who were, as Matthew Henry states it, “willingly ignorant.” “Those who will not see shall not see.” If they had but asked, He would have explained, but they never did and thus never understood. They even falsely tried to use this statement against Him at His trial (Matt 26:60-61).

Matt 13:13-14  This is why I speak to them in parables: “Though seeing, they do not see; though hearing, they do not hear or understand.  In them is fulfilled the prophecy of Isaiah: “‘You will be ever hearing but never understanding; you will be ever seeing but never perceiving.

Matt 26:60-61  But they did not find any, though many false witnesses came forward. Finally two came forward and declared, “This fellow said, ‘I am able to destroy the temple of God and rebuild it in three days.’”

The words of a prophet are verified by whether they come about or not (Deut 18:21-22). The Messiah was to die (Isa 53:5, Dan 9:26) and yet not remain in the grave (Psa 16:10). The purpose Jesus came was to die and He knew it from the beginning and yet willingly did it. Isaac was a type of Jesus except that as he was climbing the mountain, he didn’t know why. Jesus did.

Deut 18:21  You may say to yourselves, “How can we know when a message has not been spoken by the LORD?” If what a prophet proclaims in the name of the LORD does not take place or come true, that is a message the LORD has not spoken. That prophet has spoken presumptuously. Do not be afraid of him.

Isa 53:5  But he was pierced for our transgressions, he was crushed for our iniquities; the punishment that brought us peace was upon him, and by his wounds we are healed.

Dan 9:26  After the sixty-two ‘sevens’, the Anointed One will be cut off and will have nothing. The people of the ruler who will come will destroy the city and the sanctuary. The end will come like a flood: War will continue until the end, and desolations have been decreed.

Psalms 16:10  because you will not abandon me to the grave, nor will you let your Holy One see decay.

There is a great deal of irony in that the Jews will ultimately bring about the very sign for which they petitioned Jesus and that by putting Jesus to death they will destroy the very sacrificial system they were trying to defend.