The Origin of Natural Evil

"For the creation was subjected to vanity, not of its own will, but because of him who subjected it, in hope that the creation itself also will be delivered from the bondage of decay into the liberty of the glory of the children of God" (Romans 8:20-21). Disease, decay, and disaster are not treated in Scripture as features written into a good creation from the start. They are treated as a subjection — imposed, and one day to be lifted.
The most direct biblical answer traces what is often called natural evil to the curse pronounced after the fall, understood as touching the created order's own relationship to humanity, not merely as an isolated punishment falling on human beings alone. Exactly how far that subjection reaches — whether it altered the entire physical cosmos at a fundamental level, or whether certain forms of natural hardship may have existed even in the original creation outside the specific garden itself — remains a genuinely disputed question among careful readers, and Scripture does not settle every detail of it. What is affirmed without ambiguity is the direction of the whole story: death and decay are not part of God's ultimate design for creation, and they will finally be undone. No evil, including the kind popularly separated out and labeled merely "natural," is treated by Scripture as standing outside the scope of this larger conflict — or outside the scope of its eventual, total resolution.
That resolution is stated in the plainest possible terms: "He will wipe away every tear from their eyes. Death will be no more; neither will there be mourning, nor crying, nor pain, any more. The first things have passed away" (Revelation 21:4). Creation's groaning was never going to be the last word.