Death is the final examination, but there are many preliminary examinations that one must take as well. All these preliminary examinations invoke fear in the heart of those who are not prepared to pass them. Prabhupada explains that fear comes from uncertainty about one’s future. For a devotee who has taken shelter of the Lord, he knows that his future is always bright. Even in the face of adversity, because he has taken shelter of the Lord and he has experienced devotion to the Lord, he gets direct perception of the self.
LFD Vol 3,Fearlessness of the Devotee Pg 126, 7th paragraph