C.S. Lewis

But how shall I describe the other knocking? It was, in some curious way, soft; “soft as wool and sharp as death,” soft but unendurably heavy, as if at each blow some enormous hand fell on the outside of the Shoddy Sky and covered it completely. And with that knocking came a voice at whose sound my bones turned to water: “Child, child, child, let me in before the night comes.”

From Of Other Worlds: Essays and Stories  C.S. Lewis