Now the author arrives at the content of his message: why would I be afraid in difficult times?
In this instance, wrongdoers are trying to corner him. It is understandable that you become afraid when (many) enemies close in on you with the intent to rob you. He states it as a question—a kind of rhetorical question though. He counts on a negative answer: of course, I am not afraid.
5 Why should I fear in times of trouble, when the iniquity of those who cheat me surrounds me,