God having been pleased to reserve the treasure of intelligence for his children, no wonder that so much ignorance and stupidity is seen in the generality of mankind. In the generality, I include even those specially chosen, until they are ingrafted into the body of the Church. Isaiah, moreover, while reminding us that the prophetical doctrine would prove incredible not only to strangers, but also to the Jews, who were desirous to be thought of the household of God, subjoins the reason, when he asks, “To whom has the arm of the Lord been revealed?” (Isaiah 53: 1.) If at any time, then we are troubled at the small number of those who believe, let us, on the other hand, call to mind, that none comprehend the mysteries of God save those to whom it is given.
~Institutes of the Christian Religion