In the advertising business we often say that "perception is reality" for the person who views our advertising message. It does not matter whether the audience believes the message to be true, only that they perceive it to be true. Their actions will be the same whether they believe it or only perceive it.
The enemy of our souls is very good at this game. He may bring upon us what we perceive to be true when it is a lie. It may appear that there is no way around a situation. He may bring great fear upon us. When we buy into his lie, we are believing only what we have chosen to perceive to be true. It usually has no basis of truth. Such was the case when Peter looked upon the waters during a night boat journey with the other disciples. At first glance he and the disciples screamed with fear, thinking what they saw was a ghost. It was actually Jesus.
Satan’s name means "accuser". He travels to and fro to accuse the brethren. He brings an impressive front to all that he does, yet behind that front is a weak, toothless lion with a destination that has already been prepared in the great abyss. He knows his destination, but he wants to bring as many with him as possible; so he often has a big roar, but little bite.
The next time some event comes into your life that creates fear and trembling, first determine the source. Look past the emotions and evaluate in light of the word of God. Perception is not always reality.