The Enchiridion by St. Augustine
Chapter 2.--The Fear of God is Man's True Wisdom.
The true wisdom of man is piety. You find this in the book of holy Job. For we read there what wisdom itself has said to man: |Behold, the fear of the Lord [pietas], that is wisdom.| If you ask further what is meant in that place by pietas, the Greek calls it more definitely theosebeia, that is, the worship of God. The Greeks sometimes call piety eusebeia, which signifies right worship, though this, of course, refers specially to the worship of God. But when we are defining in what man's true wisdom consists, the most convenient word to use is that which distinctly expresses the fear of God. And can you, who are anxious that I should treat of great matters in few words, wish for a briefer form of expression? Or perhaps you are anxious that this expression should itself be briefly explained, and that I should unfold in a short discourse the proper mode of worshipping God?