Much has been said on fearing God and much has been said wrongly about the "Fear of the Lord".
Many who teach it talk about God as a vengeful, wrathful God who desires to burn you up and you need to fear his power or you'll get scorched.
Does God have this power? Yes, in deed He does. Has God done this in the past? Yes, in fact He has.
However is the formula (the answer to the riddle) to be afraid of God and do what is right so He doesn't scortch you? No, I believe it is not.
That formula is neither the answer to the riddle or what is mean behind the idea of "Fearing God." Does the "fear of the Lord" help us put sins in to perspective and help us along our way to sanctified living? Yes I believe it does. The true fear of the Lord does in fact lead us to repentance and does in fact lead us down a journey of jettisoning out sins that take over God's position in our lives...yet it's not due to the fear he will fry us up like an egg on a skillet but rather a right understanding of how little, how miniscule we are in the presence of a mighty God. A.W. Tozer in his book The Knowledge of the Holy says this:
"In the olden days men of faith were said to "walk in the fear of God" and to "serve the Lord with fear." However intimate their communion with God, however bold their prayers, at the base of their religious life was the conception of God as awesome and dreadful. This idea of God transcendent runs through the whole Bible and gives color and tone to the character og the saints. This fear of God was more than a natural apprehension of danger; it was a nonrational dread, an accute feeling of personal insufficiency in the presence of God the Almighty." (Tozer, 1961, p. 71)
It's not a fear of God destroying you rather it's a full on understanding of how insignificant you and I are when we are before God. Seeing how powerful, transcendent He is makes us feel week and insufficient. We realize our sheer incapacity to do anything and His omnipotence to do everything. We understand just how ugly we are and how marvelous He is.
Fearing God can then be understood as a right understanding of God and ourselves in comparison. People sin because they are acting as if they know better than God. We do what we want because we stick up our finger to God and say: "I do what I want because I'm in control" that is NOT fearing God. That's why Tozer says: "When men no longer fear God, they transgress His laws without hesitation." (Tozer, 1961, p. 71)
We we don't properly understand ourselves compared to God we will sin with abandon. When we don't fear God and see Him rightly, we will begin down a dangerous path to destruction.
Lastly, in the Proverb quoted twice above the ending says: "...and the knowledge of the Holy One is insight." (Proverbes 9:10 ESV). If fearing God is the beginning of wisdom, than seeking to know God more rightly is insight, or "understanding" as the NIV puts it. Our lives should be surrounded around Knowing God and Making Him Known.
The greatest thing about this calling is that God has left us His Spirit on the earth to indwell our hearts and make the desires come alive inside of us. We must be willing to yield our hearts over to Him so we can begin the process of seeing Him rightly, ourselves rightly and spreading His Good News whereever we go!