Heat the oven to 400 degrees, and grease a 9x13 baking dish well.
Spread half a jar of sauce into the bottom of the baking sheet.
Top the sauce with 1 bag of ravioli.
Add the remaining sauce from the first jar over the ravioli.
Sprinkle half of the mozzarella and parmesan cheese on top.
Place another layer of ½ a jar of sauce, and then the second bag of ravioli.
Spread the remaining sauce from the second jar over the ravioli, and top with the remaining cheese.
Tent a piece of tin foil over the baking sheet, and bake covered for 30 minutes.
Uncover, and bake for another 15 minutes before serving.