Brian Borgman writes:
The Bible leaves us no room for debate. The source of fear, worry, and anxiety is unbelief. The unbelief is specific, laid out for us by Isaiah and Jesus. When we fail to believe that God is for us, will take care of us, has our future in his hands, and is with us right now, we cave in to fear, worry, or anxiety…..When we are gripped with anxiety and fear, we are making an evaluation. Our souls are speaking, and our innermost being is expressing what we believe and whom we do not believe. How do we handle these emotions that can overwhelm us? We put a stranglehold on them with the vise grips of truth.
–From Chapter 11, page 128.