Job 15:23

He wandereth abroad for bread, saying, Where is it? he knoweth that the day of darkness is ready at his hand.

Wandereth in anxious search for bread. Famine in the Old Testament depicts sore need (Isaiah 5:13, "their honourable men are famished." Contrast the pious man's lot (Job 5:20). As in peace the wicked man fears the sudden attack of an enemy, so in the midst of abundance he is apprehensive of famine, and anxiously wanders to and fro in search of bread to lay up in store. The abruptness of the verse marks his restless anxiety.

Knoweth - has the firm conviction. Contrast the same word applied to the pious (Job 5:24).

Ready at his hand - an Arabic phrase, to denote a thing's complete readiness and full presence, as if in the hand.