The human race has come up with five basic answers to the question "What happens to us after we die," and God has come up with a sixth.
According to C.S. Lewis in A Grief Observed, the first five possibilities are:
1. Annihilation. Nothing. Death ends it all, except our reputation, our works, and our children, which live on after us―but we know and enjoy nothing of them if we are annihilated forever. This is a typically modern concept, although a few ancient Greek and Roman philosophers, such as Democritus and Lucretius, held it. For materialism, death is everything, because in it we become nothing.
2. We survive death, but only as ghosts. We become pale shadows of the living selves we once were. This is the mythic view of shades in Hades. It is the belief of most ancient tribes and cultures, including the early Jews and Greeks. In the mythic view, we become less than we were before death.
3. Reincarnation. We come back to earth in another mortal body. Belief in reincarnation has been popular in many times and places, including the present. It usually exists together with possibilities 4 or 5 below. In reincarnation, we become the same sort of thing we were before death.
4. The natural immortality of the soul. Each individual's disembodied spirit, liberated by death, survives as a pure spirit, like an angel. This spirit had been imprisoned in an alien thing, a body, until released forever by death. The concept is grounded in Platonism, but is often confused with Christianity, which teaches supernatural resurrection rather than natural immortality, and of the whole person, not just of the soul. For Platonism, death is nothing, as can be seen in the way Socrates faces death: as indifferently as Buddha. Whether the spirit is a universal impersonal spirit, as in Buddhism, or an individual human spirit, as in Platonism, death does not affect it, since it is radically different from the body. In Buddhism the individual body is illusion (so is the individual soul); in Platonism it is a mere prison (soma, "body," equals serna, "tomb").
5. The only thing that survives death is the only thing that was real before death: cosmic consciousness, the One, Atman, the Buddha-mind, perfect, eternal, transindividual spirit. This is the cosmic consciousness view of Hinduism and Buddhism. For Hinduism and Buddhism, death is nothing, because we already are everything, and death does not change that. It simply occurs within the all-encompassing Everything we are.
And God gives us the sixth answer:
6. Only in Christianity do we become more than we were before death. It is the startling, surprising idea of a new, greater resurrected body. As C.S. Lewis puts it in Miracles: "The records represent Christ as passing after death (as no one had passed before) neither into a purely . . . 'spiritual' mode of existence nor into a 'natural' life such as we know, but into a life which has its own new Nature. . . ." As described in the New Testament Gospels, the resurrected Jesus in the forty days before his ascension into heaven had a physical body that was solid, a body into which the doubting Thomas could put his hand to feel the wound of the spear of a Roman soldier, yet a body that could pass through solid walls into locked rooms where his frightened disciples hid.