Rinse beans and soak in a large pot of water overnight. You can also use canned beans, just keep in mind that it will taste slightly different. Another shortcut is using a pressure or slow-cooker.
In a skillet, heat oil over medium heat. Add onion, bell pepper, garlic and celery and stir for 3 to 4 minutes.
Rinse beans and transfer to a large pot adding 6 cups water. Stir cooked vegetables into beans. Add bay leaves, cayenne pepper, thyme, sage, parsley and Cajun seasoning. Bring to a boil, then reduce heat to medium-low and simmer for 2 1/2 hours.
Stir sliced sausage into beans, and continue to simmer for 30 minutes.
Serve beans over steamed white rice and enjoy some good Louisiana Red Beans and Rice!