Fides et Ratio §18

¹⁸ We may say, then, that Israel, with her reflection, was able to open to reason the path that leads to the mystery. With the Revelation of God Israel could plumb the depths of all that she sought in vain to reach by way of reason. On the basis of this deeper form of knowledge, the Chosen People understood that, if reason were to be fully true to itself, then it must respect certain basic rules. The first of these is that reason must realize that human knowledge is a journey which allows no rest; the second stems from the awareness that such a path is not for the proud who think that everything is the fruit of personal conquest; a third rule is grounded in the “fear of God” whose transcendent sovereignty and provident love in the governance of the world reason must recognize. In abandoning these rules, the human being runs the risk of failure and ends up in the condition of “the fool”. For the Bible, in this foolishness there lies a threat to life. The fool thinks that he knows many things, but really he is incapable of fixing his gaze on the things that truly matter. Therefore he can neither order his mind ( Prov 1:7) nor assume a correct attitude to himself or to the world around him. And so when he claims that “God does not exist” (cf. Ps 14:1), he shows with absolute clarity just how deficient his knowledge is and just how far he is from the full truth of things, their origin and their destiny.