And if Christ has not been raised, your faith is worthless; you are still in your sins. (1 Corinthians 15:17)
Surprisingly, many people who say that they believe in God and that Jesus is their savior, question or even deny His bodily resurrection. This heresy began in some of the early New Testament churches who were influenced by the Sadducees, a Jewish sect of Priests who denied the resurrection of the dead. Unfortunately, many people today still believe that it doesn't matter as long as you have faith in Jesus.
However, scripture clearly tells us that to deny the resurrection of Christ is to deny the gospel and salvation in Christ; And if Christ has not been raised, your faith is worthless; you are still in your sins. The bodily resurrection of Christ (not just His spiritual resurrection), is the demonstration that God has accepted His sacrificial offering and atonement for our sins.
The bodily resurrection of Christ also gives credence to God's promises regarding our future bodily resurrection; But now Christ has been raised from the dead, the first fruits of those who are asleep. (1 Corinthians 15:20)
...But each in His own order; Christ the first fruits, after that those who are Christ's at His Coming. (1 Corinthians 15:23)