Gospel commented, "He was speaking about the temple of his body" John 2:13-25.

Since the Passover of the Jews was near, Jesus went up to Jerusalem. 
He found in the temple area those who sold oxen, sheep, and doves, as well as the money-changers seated there.
He made a whip out of cords and drove them all out of the temple area, with the sheep and oxen, and spilled the coins of the money-changers and overturned their tables, 
and to those who sold doves he said, "Take these out of here, and stop making my Father's house a marketplace." 
His disciples recalled the words of scripture, "Zeal for your house will consume me."
At this the Jews answered and said to him, "What sign can you show us for doing this?" 
Jesus answered and said to them, "Destroy this temple and in three days I will raise it up."
The Jews said, "This temple has been under construction for forty-six years, and you will raise it up in three days?"
But he was speaking about the temple of his body. 
Therefore, when he was raised from the dead, his disciples remembered that he had said this, and they came to believe the scripture and the word Jesus had spoken. 
While he was in Jerusalem for the feast of Passover, many began to believe in his name when they saw the signs he was doing. 
But Jesus would not trust himself to them because he knew them all, 
and did not need anyone to testify about human nature. He himself understood it well.

"He was speaking about the temple of his body"

“Destroy this temple and in three days I will raise it up.” … In my view, both the temple and Jesus’ body are a symbol of the Church… The temple will be rebuilt and the body will rise on the third day… For the third day will rise in a new heaven and a new earth (2 Pet 3,13) when the dry bones, that is to say the whole house of Israel (Ezek 37,11), will stand up on the great Day of the Lord and death will be vanquished…

Just as the body of Jesus, subject to our vulnerable human condition, was fastened to the cross and buried and then raised up, so the whole body of Christ’s faithful  was “fastened to the cross with him” and “now no longer lives” (Gal 2,19). For, like Paul, not one of them glories in anything any longer but in the cross of our Lord Jesus Christ, which made of him one crucified for the world and made of the world one crucified for him (Gal 6,14)… “For we were buried with Christ,” Paul says, and adds, as if he had received some pledge of the resurrection: “And have been raised to life again with him” (Rom 6:4-9) Everyone is walking in a new life therefore, but this new life is not yet the happy and perfect resurrection… If anyone is now placed in the tomb, one day he will rise again.