Rinse beans, and then soak in a large pot of water overnight.
In a frying pan, heat oil over medium heat. Cook onion, pepper, garlic and celery in olive oil for 3 to 4 minutes.
Rinse beans, and transfer to a large pot with water. Stir cooked vegetables into beans. Season with bay leaves, cayenne pepper, thyme, sage, parsley and Cajun seasoning. Bring to the boil, then reduce heat to medium-low. Simmer for 2 1/2 hours.
Stir sausage into beans, and continue to simmer for 30 minutes.
Meanwhile, prepare the rice. In a saucepan, bring water and rice to the boil. Reduce heat, cover, and simmer for 20 minutes. Serve beans over steamed white rice.