Rinse the dried green peas under cold water. Place them in a large bowl and cover with water. Let soak overnight, or at least 8 hours.
Drain and rinse the soaked peas. In a large pot, combine the peas with 8 cups of fresh water.
Bring to a boil, then reduce the heat to low and simmer for 30 minutes, or until the peas are tender.
Add the ham hock or diced ham, chopped onion, minced garlic, diced carrots, and diced celery to the pot.
Stir in the dried thyme and bay leaf.
Continue to simmer the soup for about 1-1.5 hours, or until the peas have broken down and the meat is tender. Stir occasionally.
Remove the ham hock if used. If desired, shred the meat from the bone and return it to the soup.
Season with salt and black pepper to taste.
Garnish with fresh chopped parsley.
Enjoy your meal!