How does the concept of duality contribute to fear, and what is the prescribed solution?

As detailed in Chapter 37, fear is directly linked to the perception of duality. The text states that where there is an obsession with duality, fear inevitably enters. He who holds even the slightest view of difference or separation will fall into the sufferings of birth and death. The solution is to serve the non-distinguished state, where there is not even a trace of fear. This is achieved through the science of the oneness of Brahman and the Self, which is the ultimate means to liberation and the cessation of birth and death.