Fear In A Handful Of Dust By T. S. Elliot

T.S. Elliot is explaining that fear is invaluable and we put too much time into the concept of “fear”. He uses the notion of fear in “I will show you fear in a handful of dust” which explains that it (fear) is often exaggerated which is why it has being compared to the very simple object of dust. This quote also uses concepts of day and night to describe how one's perspective can change “Your shadow at morning striding behind you Or your shadow at evening rising to meet you” meaning that your shadow can be in front of you in the morning when you first wake up, but at night when you go to sleep it is often behind you.
This epigraph contains a metaphor relating dust to the abstract idea of fear. Dust can be compared to fear because dust is small