What's a miracle?

‘The Greek word for miracles is “simaios” which means sign. Miracles are signs, and like all signs, they are never about themselves; they’re about whatever they are pointing towards. Miracles point beyond themselves. But to what? To God himself. That’s the point of miracles- to point us beyond our world to another world. They are clues that the other world is not in our imaginations but is actually out there, wherever “out there” actually is.  Peggy Noonan once wrote that she thought miracles existed “in part as gifts and in part as clues that there is something beyond the flat world we see” If miracles exist at all, they exist not for their own sake but for us, to point us toward something beyond. To someone beyond’

Miracles, Eric Metaxas, Page 16

I am really enjoying reading this and it's a book sceptical friends and interested seekers might find compelling.