When discussing God's existence, critics/atheists will often make the argument, "How could a good God create people in a world with so much pain? Why would he make humans in the first place if they were just going to suffer?" Many answers have been offered for this, not least of which is that free will necessitates the element of choice - choosing good vs. evil - which therefore creates an opening for evil, pain, etc. in the world. But another answer, and I think perhaps a more convincing one, is this: Human frailty is actually evidence of eternity.
Why would God create people in a world with so much pain? Because the world was originally created to be a paradise, free from pain and anxiety and fear of any kind. Our existence began in the Garden of Eden, not in this sad, crippled, broken place we now inhabit.
In this original state of edenic perfection, humans were designed to live forever. Our bodies would not wear out. We would perhaps still age, but not in a deteriorating way. We would always be strong, always be healthy, always be whole. We would never get headaches, heart disease, sunburn, frostbite, dementia, depression, or cancer. All this was, of course, lost when Adam and Eve's pride cost them their place (and ours) in Eden.
But God did not just create humans with bodies; He also gave us souls. As C. S. Lewis famously said, "You don't have a soul. You are a soul. You have a body." So while the body suffers a great deal in this life on earth, this is not a permanent state. When the body dies, the soul will go on to either be forever happy in heaven or forever tormented in hell.
Human frailty is actually undeniable evidence of eternity. If we were made for this world only, why would God give us such fragile, easily damaged bodies? The answer is that he would not. And he did not. He gave us elegant, perfect, unbreakable bodies, and he put us in a world where these bodies would have nothing to hurt them. But then the Fall of Man happened, and the curse was unleashed. Hands meant for endless pleasure and painless work now had to endure blisters, burns, bruises, broken bones, age, and arthritis. Feet designed for running in the cool grass and walking next to the Creator would now be crippled by callouses, splinters, blisters, gout, infected nails, and sprained ankles. Lungs meant to breathe pure air in a paradise would now be subjected to allergies, asthma, pneumonia, and consumption. Brains made for processing joy and delight would now be plagued by debilitating fear and overwhelming darkness.
Our bodies are now so incredibly fragile, so easily damaged. Nobody would disagree with this fact. And yet few people would see this as evidence of eternity, of the time when our broken bodies will be restored and renewed . . . when we will return to paradise.
Evolution is often touted as something that converts needs into abilities. For example, a rabbit needs to blend into his surroundings, so he develops the ability to change fur color (brown in summer, white in winter). Or a fish needs to cross dry land, so he develops legs to walk. But if it were as simple as this, why wouldn't humans have developed abilities to meet our needs? Why are our bodies not stronger, faster, more durable, less fragile? Because in their original design, they were all those things and more. We have not gained new abilities because our old abilities are still there, dormant as seeds in the frozen winter soil. It's not our bodies that have changed but the environment where they exist. The Garden of Eden was lost, and we were left to live in a harsh, cursed, broken world. But when we are placed back in an environment of perfection (when we reach heaven), our bodies will be restored to their original state. The earth will thaw, and the seeds will sprout once again.
At least, that's one option - the option God wants for us. The other option is hell, where everything is even worse than it is on earth, where the effects of the curse will be uninhibited and unending. In hell, pain will be continuous, uninterrupted. Suffering, burning, agony . . . forever.
A human being is a wondrous thing. It was God's piece de resistance, his final and greatest creation. It was not just good but very good. And someday, our bodies will return to their intended state . . . when our souls return to their home, to the presence of the Almighty, where there is no need for the sun because his glory illuminates all of heaven.
Our frailty is evidence of our eternity. But we must die to be reborn. We must leave this broken place to reach that perfect place. O Death, where is your victory? The death of our fragile bodies is just the means to their ultimate restoration. As our Lord Jesus said, for those who believe, "Today you will be with me in paradise."