23 But you will, perhaps, say that the gods are not artificers, but that they preside over these arts, and have their oversight; nay, that under their care all things have been placed, which we manage and conduct, and that their providence sees to the happy and fortunate issue of these. Now this would certainly appear to be said justly, and with some probability, if all we engage in, all we do, or all we attempt in human affairs, sped as we wished and purposed.
But since every day the reverse is the case, and the results of actions do not correspond to the purpose of the will, it is trifling to say that we have, set as guardians over as, gods invented by our superstitious fancy, not grasped with assured certainty. Portunus gives to the sailor perfect safety in traversing the seas; but why has the raging sea cast up so many cruelly-shattered wrecks? Consus suggests to our minds courses safe and serviceable; and why does an unexpected change perpetually issue in results other than were looked for?
Pales and Inuus are set as guardians over the flocks and herds; why do they, with hurtful laziness, not take care to avert from the herds in their summer pastures, cruel, infectious, and destructive diseases? The harlot Flora, venerated in lewd sports, sees well to it that the fields blossom; and why are buds and tender plants daily nipt and destroyed by most hurtful frost? Juno presides over childbirth, and aids travailing mothers; and why are a thousand mothers every day cut off in murderous throes?
Fire is under Vulcan's care, and its source is placed under his control; and why does he, very often, suffer temples and parts of cities to fall into ashes devoured by flames? The soothsayers receive the knowledge of their art from the Pythian god; and why does he so often give and afford answers equivocal, doubtful, steeped in darkness and obscurity? Aesculapius presides over the duties and arts of medicine; and why cannot men in more kinds of disease and sickness be restored to health and soundness of body?
While, on the contrary, they become worse under the hands of the physician. Mercury is occupied with combats, and presides over boxing and wrestling matches; and why does he not make all invincible who are in his charge? Why, when appointed to one office, does he enable some to win the victory, while he suffers others to be ridiculed for their disgraceful weakness?
Source: Against the Heathen (New Advent)