1. In a large saucepan, cover beans with water. Bring to a boil and cook 3 minutes.
2. Remove from heat, cover and let stand 1 hour.
3. Return pan to medium heat and add chicken, onion and celery. Cook 1 hour.
4. Remove chicken. Add barley; season with pepper, mustard and cayenne.
5. Cook 30 minutes, until beans and barley are tender.
6. Remove chicken from bones and shred meat. Return meat to soup.