In a deep skillet, combine the mussels, sherry and wine. Bring to a simmer, cover and cook over moderate heat until the mussels open, 3 minutes. Remove the mussels from their shells. Strain the broth; reserve 1 cup.
Wipe out the skillet and heat the olive oil in it. Add the garlic and chile and cook over moderate heat for 1 minute. Stir in the beans. Add the broth, season with salt and bring to a boil. Add the mussels and the parsley and heat through. Serve the stew with crusty bread.