what is going on when elisenda and pelayo first discover the stranger?

The short story, A Very Old Man With Enormous Wings tells the story of Pelayo and his wife Elisenda, who find an old man with wings in their courtyard after killing crabs in a rainstorm. Pelayo gets his wife, and they try to communicate with him unsuccessfully. They eventually get their neighbor woman, who informs them that the old man is an angel. She tells them that it was on its way for their sick child.