Some Christians don't believe in the resurrection of the human body when Christ returns. They've been influenced by the ancient philosophers, such as Plato, who taught that the soul was the main part of human life and that death rids humans of the body so they can enjoy soul-life in the hereafter (See an interesting article here: https://zondervanacademic.com/blog/death-afterlife-greco-roman-antiquity  Paul wrote about such Christians in 1st Corinthians 15:12, "But if it is preached that Christ has been raised from the dead, how can some of you say that there is no resurrection of the dead?" Then he said, "For if the dead are not raised, then Christ has not been raised either. And if Christ has not been raised, your faith is futile; you are still in your sins." 1st Cor. 15:16-17 NIV) So, it's clear that the bodily resurrection is part of the gospel. In fact, it's a major part of the good news, the gospel. That's why the apostle Paul wrote about the gospel in 1st Corinthians 15:1-4 and then spent the rest of that chapter teaching them about the resurrection. Want to learn more?