A Big thanks to @sirknight for initiating this challenge.
Darkness is characterised by so many things:
It can be regarded as something hidden as in the case of idiomatic expression. Example, the issue was kept in the dark.
It is a time when no man can work.
Meaning - old age. Jesus referred to it in
John 9:4
I must work the works of him that sent me, while it is day: the night cometh, when no man can work.
It signifies when evil and it is opposite of light which signifies good. Darkness and light has no connection.
In 2 corinthians 6:14 the bible says
Do not be unequally yoked with unbelievers. For what partnership has righteousness with lawlessness? Or what fellowship has light with darkness?
Darkness involves sleep and time to rest after the day's work.
It is also the final destination of the evil doers-"cast into outer darkness where there is gnashing of teeth.
Luke 13:28
"There will be weeping there, and gnashing of teeth, when you see Abraham, Isaac and Jacob and all the prophets in the kingdom of God, but you yourselves thrown out.
It is a time to make use of light to see so as not to bump into objects.