In the King James Version Bible, the word 'fear' did not mean, as it does today, 'to be scared of'. Rather, it meant 'have deep respect for'.
Therefore one should fear God - in other words, respect God for who he is - show him respect and honour and love. In the same Bible, we are also asked to fear our parents - not to be scared of them (!!!) but to show them the respect they should receive from us.
The word for fear here means "reverential fear." It means that one must be serious about their relationship to God. People who "fear" the Lord are not anxious about their relationship to him, or afraid of Him, they take very seriously their responsibility to Him.
Hebrews 11:7
"By faith Noah, being warned of God of things not seen as yet, moved with fear, prepared an ark to the saving of his house; by the which he condemned the world, and became heir of the righteousness which is by faith."
Do not fear, for I am with you; do not be dismayed, for I am your God. I will strengthen you and help you; I will uphold you with my righteous right hand