The sign of the Temple
Destroy this Temple and in three days I will raise it up again.
To be sure, the Savior was capable of showing thousands of other signs, but to show "why he was acting like this" none other was possible. That is why, very appropriately, his answer concerned the Temple rather than other signs without any connection to it. Nevertheless, it seems to me that the Temple and the body of Jesus should be interpreted as a symbol of the Church since the latter is built with “living stones, a spiritual building for a holy priesthood.†It is built “upon the foundation of the apostles and prophets with Christ Jesus as the cornerstone,†the true temple.
Since you are Christ's body and individually parts of it", even if we witness the stones of the temple, strongly compact, destroyed and, as it is written in Psalm 21[22], we see all Christ's bones racked under the assault of his trials and tribulations. . . and the persecutions that come together against the temple's unity, yet the temple will be raised up and the body will rise again on the third day after the day of iniquity, which would have destroyed it, and after the day of fulfilment that is to follow. For there will be a third day in a new heaven and new earth when the dry bones. . . will stand up on the Day of the Lord following his victory over death. Christ's resurrection, following his Passion and his cross, embraces the whole mystery of the resurrection of Christ's Body.
(Biblical references: Jn 2,18-19; 1P 2,5; Ep 2,20; 1Co 12,27; Ps 21,15; 2P 3,3-10.13; Ez 37,11)
St. Robert Bellermine