In the Harvard Divinity Bulletin, Karen Armstrong on religion and immortality:
Religion is about transformation; by ritual and ethical practice we become fundamentally different. Religion is not about preparing for the beatific vision in Heaven; it is also about living a fully human life in this world. By becoming one with these paradigmatic figures, losing our flawed, everyday selves in their perfection, we too can become perfect and inhabit an eternal dimension even in this world of pain and death.
Like any other religious truth, immortality must become a present reality. It is liberation from the constraints of time and space, and from the limitations of our narrow horizons. It involves a profound realization that the deepest core of our being is inseparable from what has been called God, nirvana, brahman, or the Dao. Like any myth, it is a program for action. The traditions teach us how to effect this radical internal transformation; they cannot tell us what this immortal state is, because it is so different from our normal consciousness that it is ineffable, but they provide us with a method that will help us to change. Unless we put that method into practice, we are in no position to say whether we have an immortal self or not. Immortality is not a matter of waiting for the next life, but in perfecting our humanity here and now.
Not many of the world religions are as preoccupied with Heaven, Hell, and judgment as Christianity and Islam; these faiths absorbed much of the apocalyptic vision of Zoroastrianism, which was unique in the ancient world. Many of the great sages were wary of speaking about the afterlife. The afterlife has never been a major preoccupation in Judaism. St. Paul told his converts, “Eye hath not seen, ear hath not heard, nor has it entered into the heart of man what things God has prepared for those that love him.” When asked whether a Buddha who had achieved the enlightenment of nirvana continued to exist after his death, the Buddha replied that this was an improper question, because we have no words to describe this state. It was, therefore, pointless to discuss it.