This represents the heart of the debate between futurism and preterism. The death that Jesus came to defeat is the death that entered in the garden, the death Adam experienced the day he ate of the fruit. When Adam ate, he lived for another 900 years and had children, one who died physically before he did. Thus, the death Adam died was not physical, but spiritual: he became separated from God. Thus, the death Jesus came to defeat is not physical death, but spiritual. Bodies are still in graves after the resurrection has taken place because the Bible does not speak about the resurrection of physical bodies, but reunion between God and man, made possible through the death, burial, and resurrection of Jesus.