Jehovah's Witnesses do not believe in Christ's bodily resurrection: Is it really that important?

John 2:18-21 says:

'Destroy this temple and in three days, I will raise it up." The Jewish leaders said, "It took 46 years to build this temple and you're going to raise it again in three days?" But He was speaking of the temple of His BODY.

But the Watchtower says:
"According to the inspired Scriptures, Jesus Christ was not raised to life in the flesh " (Watchtower 8/1/1975 p. 478)

Why is this important? 

We can see why at 1 Corinthians 15:14-17:
If Christ is not risen, then our preaching is empty and your faith is also empty. 
Yes, and we are found false witnesses of God, because we have testified of God that He raised up Christ, ...
And if Christ is not risen, your faith is futile; you are still in your sins!

and Romans 4:25:
Jesus our Lord was delivered up because of our offenses, and was raised because of our justification. (New King James Version)

He was delivered up for the sake of our trespasses and was raised up for the sake of declaring us righteous. (New World Translation)

If you need more information on the term justification please look up the Greek word dikaiósis: http://biblesuite.com/greek/1347.htm

Once again, lets compare the teachings of Jehovah's Witnesses with God's Word:

Chapter 17 of "You can Live Forever in Paradise on Earth" talks extensively of Jesus resurrection, saying:   "Having given up his flesh for the life of the world, Christ could never take it again and become a man once more... when Christ was raised from the dead, his fleshly body was no longer in the tomb. (Mark 16:5-7) Also, after his death Jesus appeared to his disciples in a fleshly body to show them that he was alive. Once He even had the apostle Thomas put his hand into the hole in His side so that Thomas would believe that He had actually been resurrected. (John 20:24-27) Does this not prove that Christ was raised alive in the same body in which he was put to death? No, it does not."

Luke 24: 34-40: “While they were speaking of these things [the Lord] himself stood in their midst ...But they were imagining they beheld a spirit. So he said to them: “Why are ​YOU​ troubled, and why is it doubts come up in ​YOUR​ hearts? See my hands and my feet, that it is I myself; feel me and see, because a spirit does not have flesh and bones just as ​YOU​ behold that I have.” [[And as he said this he showed them his hands and his feet.]]

 

Will you believe God's Word over that of man's?