'Darkness' in the Bible

So I did just as I was commanded. I carried out my belongings packed for exile during the day, and at evening I dug myself a hole through the wall with my hands. I went out in the darkness, carrying my baggage on my shoulder while they watched.

"The prince who is among them will raise his belongings onto his shoulder in darkness, and will go out. He will dig a hole in the wall to leave through. He will cover his face so that he cannot see the land with his eyes.