The Divine Institutes

But this consideration may perhaps have influenced them, that if there were any true religion, it would exert itself and assert its authority, and not permit the existence of anything opposed to it. For they were unable to see at all, on what account, or by whom, and in what manner true religion was depressed, which partakes of a divine mystery and a heavenly secret. And no man can know this by any means, unless he is taught. The sum of the matter is this: The unlearned and the foolish esteem false religions as true, because they neither know the true nor understand the false. But the more sagacious, because they are ignorant of the true, either persist in those religions which they know to be false, that they may appear to possess something; or worship nothing at all, that they may not fall into error, whereas this very thing partakes largely of error, under the figure of a man to imitate the life of cattle.

To understand that which is false is truly the part of wisdom, but of human wisdom. Beyond this step man cannot proceed, and thus many of the philosophers have taken away religious institutions, as I have pointed out; but to know the truth is the part of divine wisdom. But man by himself cannot attain to this knowledge, unless he is taught by God. Thus philosophers have reached the height of human wisdom, so as to understand that which is not; but they have failed in attaining the power of saying that which really is.

It is a well-known saying of Cicero: “I wish that I could as easily find out the truth as I can refute false things.” And because this is beyond the power of man's condition, the capability of this office is assigned to us, to whom God has delivered the knowledge of the truth; to the explaining of which the four last books shall be devoted. Now, in the meantime, let us bring to light false things, as we have begun to do.