Fear is a major role in how people handle their business.
For example, fears and phobias can prevent a person from doing something, or going somewhere, or participating in some kind of event.
It can manifest from a small entity of life to a larger part of your personality.
Why be afraid?
What is there to be afraid of?
Fear can eat up time. It can destroy relationships. It can prolong distress. It can cause anxiety.
In Islam we are taught to only Fear God. To fear Him is to ask Him for protection, to rely solely on His aide, to seek His Wisdom and to take responsibility for our actions.
In Surah Kahf, there is an example of the Sleepers in the Cave who escaped from their homeland in fear of losing their religion, and out of love for the sake of worshiping God.
They said, '"Our Lord! Bestow on us mercy from Yourself, and facilitate for us our affair in the right way!'"
The Sleepers then woke up after 300 years (years debated) to find themselves in a safer environment.
Therefore, fearing Him means relying on Him.
When we commit sin, fear means understanding our connection to God. It means repenting. It means coming back to him. It means getting closer to Him, and getting to know ourselves better.
Fear can be beautiful when there is a balance with love. The balance is called taqwa, belief.
"Those who answered (the Call of) Allah and the Messenger (Muhammad ) after being wounded; for those of them who did good deeds and feared Allah, there is a great reward... Those (i.e. believers) unto whom the people (hypocrites) said, "Verily, the people (pagans) have gathered against you (a great army), therefore, fear them."
But it (only) increased them in Faith, and they said: 'Allah (Alone) is Sufficient for us, and He is the Best Disposer of affairs (for us).' (3:171-173)"
Destiny is written. In the book "Don't Be Sad" by Adullah Aaidh Al-Qarni, he said, what is meant to happen will surely come to pass. Don't get trapped by what you think will /can happen in the future.
What is there to be afraid of when we have God by our side?