We think of fear as a negative emotion, so we try to eliminate it. We therefore lose sight of the fact that fear can also be constructive. Fear motivates us to drive cautiously even when in a great hurry, and fear makes a diabetic adhere to his diet and take his insulin daily.
Religion has often been criticized for advocating the fear of God. This criticism may be justified if we were conditioned to think of Him as an all-powerful Being holding a huge club, ready to beat a sinner to a pulp for doing something wrong. All ethical works discourage the use of this type of fear as motivation. Rather, fear of God should be understood to mean the fear of the harmful consequences that are inherent in violating His instructions. The Psalmist says that wickedness itself destroys the wicked person (see Psalms 34:22).
"Fortunate is the person who fears God," in the sense that "he has great desire for His mitzvos" (Psalms 112:1). It is only natural for one to desire the very best, and the realization that observing the mitzvos is indeed in one's best interest should constitute the "fear" that should deter someone from transgressing the Divine will.