In a large saucepan over medium high heat, combine the soaked lima beans, carrots, celery, tomatoes and water. Bring to a boil. Reduce the heat and simmer partially covered until beans and vegetables are tender, about 1 hour. If using canned beans, add at the end of the recipe. In a small skillet over low heat, melt the butter. Add the onion and parsley, cook until the onion is soft, about 5minutes. Stir in flour and cook for 1 minute. Stir the mixture into soup and simmer until the soup is slightly thickened, about 5 minutes. Season with salt and pepper. Makes 4 cups