While I do not hold to an allegorical interpretation of Scripture, there are some passages that can be read in an allegorical manner.
Night - hebrew word for literal night, but also for adversity.
Similarly the word Darkness - literally meaning of night darkness or blindness. Metaphorically darkness speaks of ignorance.
Soldiers describe the night before a battle as the longest night of their lives.
Psychologically there is something about darkness that oppresses us and makes us feel cut off and alone.
Spiritually this same thing happens. When we let night into our souls our spirits begin to feel cut off. We find ourselves walking in fear and being moved by circumstances. If left unchecked we soon begin to speak and act no differently from anyone else in the world. The Bible refers to this as putting your lamp under a basket. We hide the light keeping ourselves and those around us in the dark.