This verse is plucked out alone to showcase how deep a faithful person's despair can become. Job uses two words for darkness in this verse which he uses previously in his speeches to talk about death, separation from God, Sheol, and uncreation. Although he has had some fantastic confessions in the faith of hope in the resurrection and the Redeemer so he may enjoy God's blessings, he is sorrowful now. Job feels like he can't even see God. However, just beyond the veil of darkness, God is still present with him--as God is present with all people in faith--and delivering Job unto everlasting life and blessedness.