Preheat your oven to 350°F (175°C).
In a skillet over medium heat, sauté the chopped celery and onion in melted butter until they turn translucent.
Add the minced garlic, dried thyme, and dried sage. Sauté for an additional 2 minutes until fragrant.
In a large mixing bowl, combine the bread cubes and the sautéed mixture.
Gently fold in the chopped oysters, chopped parsley, and a pinch of salt and pepper.
Gradually pour in the chicken or vegetable broth, stirring gently to ensure everything is well combined.
Transfer the mixture into a greased baking dish, spreading it evenly.
Bake in the preheated oven for about 45-50 minutes, until the top is golden brown and the dressing is cooked through.
Once done, remove from the oven and let it cool slightly before serving.