From John A. Kitchen's commentary on Proverbs:
One will never know God without first fearing Him. No one will fear Him without knowing something of Him. To know God is to fear Him. to rightly fear God is to grow in knowledge of Him. Indeed, fear of the Lord and the knowledge of God are often found as the twin towers of true religion (Isa. 11:2; 58:2)...
To possess the 'fear of the Lord' is to embrace reality. It signals the adoption of a Biblical worldview. It defines the perspective of the person who has come to see that 'The earth is the Lord's and all it contains, The world, and those who dwell in it' (Ps. 24:1). It describes an informed and accurate perspective of who God is and who I am before Him.
To possess the fear of the Lord is to embrace reality.
What is the flip side of that? To reject the fear of the Lord is to be deluded. It is very reminiscent of Romans 1:18-32.
Fear of the Lord establishes who is in control and who is not. It affects how I regard my life, my possessions, other people, the circumstances I find myself in, what's going on in the world around me; everything.