No reflection was to be allowed now, not one glance was to be cast back; not even one forward. Not one thought was to be given either to the past or the future. The first was a page so heavenly sweet, so deadly sad, that to read one line of it would dissolve my courage and break down my energy. The last was an awful blank, something like the world when the deluge was gone by.

– Charlotte Bronte

Jane Eyre, Chapter 27. Jane looks back on the life she has left at Thornfield, full of comfort and love, and contrasts it to the unknown and uncertain one she is going to. She uses a metaphor to compare her past and future to two very different pages.