Heat 4 tbsp of the oil in a large skillet over medium heat; add thyme sprigs and chopped walnuts and cook for 2-3 minutes until walnuts are fragrant.
Cook the ravioli according to package instructions and drain, reserving ½ cup of the pasta cooking water. Transfer the pasta to the pan adding the orange juice and a little of the pasta cooking water to loosen the sauce, if needed, then add the remaining oil and the orange zest and toss to combine. Season with salt and pepper to taste. Divide among plates and serve.