In the bedroom upstairs (the priority Ring unlocks it) examine the dresser to get a poem that contains clues to how the dics get rotated. You will also find the Vulcan Statue in the bottom drawer (again, unlocked with the priority ring). head back downstairs and check out the stained glass window with the fleur-de-lis on it.
Each of those fleur de lis represent each god, as does each line of the poem. Go back to the discs and (using the tip of the fleur-de-lis as the top) turn the discs so that they are pointing down, right, up, left in that order. This should open the lion's mouth and net you the Venus Statue.