And this is the message which we heard from Him and announce to you, that God is light and in Him is not any darkness, 1 John 1:5.
Darkness is where light does not reside; therefore, it is where unrighteousness and sin dwell, and where demons play. The one true God has no darkness in Him, for He cannot be tempted to do wrong, because He never acts in a manner contrary to Who He truly is; therefore, He does not hide His actions (1 Timothy 6:16; James 1:13). Lucifer rejected the light and chose to act independently of God, desiring to set his throne in the third heaven with God (Isaiah 14:13). His sin brought about the kingdom of darkness, where he now rules, as he seeks to hide who he truly is and to display himself as a messenger of light (2 Corinthians 11:14)—a kingdom to which all the unsaved belong because of Adam’s sin and condemnation (Colossians 1:13–14).