(53) The sphere of reason is, as we have said, truth and wisdom; the sphere of theology, is piety and obedience. (54) The power of reason does not extend so far as to determine for us that men may be blessed through simple obedience, without understanding. (55) Theology, tells us nothing else, enjoins on us no command save obedience, and has neither the will nor the power to oppose reason: she defines the dogmas of faith (as we pointed out in the last chapter) only in so far as they may be necessary for obedience, and leaves reason to determine their precise truth: for reason is the light of the mind, and without her all things are dreams and phantoms.
(56) By theology, I here mean, strictly speaking, revelation, in so far as it indicates the object aimed at by Scripture namely, the scheme and manner of obedience, or the true dogmas of piety and faith. (57) This may truly be called the Word of God, which does not consist in a certain number of books (see Chap. XII.). (58) Theology thus understood, if we regard its precepts or rules of life, will be found in accordance with reason; and, if we look to its aim and object, will be seen to be in nowise repugnant thereto, wherefore it is universal to all men.
(59) As for its bearing on Scripture, we have shown in Chap. VII. that the meaning of Scripture should be gathered from its own history, and not from the history of nature in general, which is the basis of philosophy.
(60) We ought not to be hindered if we find that our investigation of the meaning of Scripture thus conducted shows us that it is here and there repugnant to reason; for whatever we may find of this sort in the Bible, which men may be in ignorance of, without injury to their charity, has, we may be sure, no bearing on theology or the Word of God, and may, therefore, without blame, be viewed by every one as he pleases.
(61) To sum up, we may draw the absolute conclusion that the Bible must not be accommodated to reason, nor reason to the Bible.
(62) Now, inasmuch as the basis of theology - the doctrine that man may be saved by obedience alone - cannot be proved by reason whether it be true or false, we may be asked, Why, then, should we believe it? (63) If we do so without the aid of reason, we accept it blindly, and act foolishly and injudiciously; if, on the other hand, we settle that it can be proved by reason, theology becomes a part of philosophy, and inseparable therefrom. (64) But I make answer that I have absolutely established that this basis of theology cannot be investigated by the natural light of reason, or, at any rate, that no one ever has proved it by such means, and, therefore, revelation was necessary. (65) We should, however, make use of our reason, in order to grasp with moral certainty what is revealed - I say, with moral certainty, for we cannot hope to attain greater certainty than the prophets: yet their certainty was only, moral, as I showed in Chap. II.
(66) Those, therefore, who attempt to set forth the authority of Scripture with mathematical demonstrations are wholly in error: for the authority of the Bible is dependent on the authority of the prophets, and can be supported by no stronger arguments than those employed in old time by the prophets for convincing the people of their own authority. (67) Our certainty on the same subject can be founded on no other basis than that which served as foundation for the certainty of the prophets.
(68) Now the certainty of the prophets consisted (as we pointed out) in these elements:-
(69) (I.) A distinct and vivid imagination.
(70) (II.) A sign.