William Temple once remarked to Bertram Russell, that he believed in life after death much more strongly than the evidence warranted. Russell replied that he disbelieved it much more than the evidence warranted. This amusing exchange between intellectuals with opposing world views underlines the fact that life beyond this one--or lack thereof--cannot be proven. Faith is required on both sides of the proposition.
Believers reason that if death is the end, a universe that produced human consciousness with aspirations going beyond what this life provides, is cruel and absurd. But why should the universe NOT be cruel and absurd? Atheist thinkers have asked this question. Jean Paul Sartre affirms the non-sensical nature of reality and encouraged humans to grope their way forward, making value choices which they know are valueless.
Christians believe that the universe is rational. This is a faith which also finds expression as hope. Hope that self-conscious life--having been brought to be by a loving God who desires to be loved--will not peter out into oblivion. Hope such as this enables the subject to look on death through different eyes. A lifetime, short or long, in which personal qualities have taken shape, been striven for, prized, admired and become the object of affection and devotion, invite us to think that, love and human relationships ought not be unilaterally terminated. Spiritual realities which go to make up personality are suggestive of an extra-material existence beyond death's reach. If beyond death, an eternal vacuum broods, then the inevitable parting which awaits every human bonding, is terrible in its bleakness.
Jesus Christ invites us to believe that those instincts of ours have a basis in reality. Scripture also teaches that whom God sets his love upon, he will never let go--in this world, and the next.
"Brothers, we do not want you . . . . to grieve like the rest of men who have no hope" (1 Corinthians 4:13).