The clergyman Mr. Maydig is very impressed with Fotheringay's miracle-working abilities—so much so that the challenges him to make the earth stand still and stop time. Foolishly, Fotheringay accedes to Maydig's request, asking for the earth to stop rotating. (Later, he asks to be brought back down to earth safe and sound.)
The earth duly grinds to a halt, and, as we might expect, people, animals, and things of various kinds start flying through the air. Fotheringay is one of them, but thanks to his miracle-working abilities, he is able to survive. However, the same can't be said of anyone else, because thanks to this particular miracle, every living thing on the planet has been completely destroyed and will remain destroyed until Fotheringay "undoes" all his miracles at the end of the story.