Several years ago, I was working on replacing an old, falling-over retaining wall on the side of my house. Some of the stones I replaced were too big for me to move and some were cemented together into “blobs” of rock and concrete. So I set out to bust them up with a sledge hammer. I struck those rocks with the sledge hammer a hundred times, each time I hit the rock it would make a specific sound, each time the same sound. But eventually after dozens of strikes, the sound changed in pitch. The next blow split the rock in two. Prayer often seems to work that way. We can think that nothing is happening, but every blow contributes to the final blow.