A warning to those who substitute darkness for light
“Woe to those who call evil good, and good evil; Who substitute darkness for light and light for darkness; Who substitute bitter for sweet and sweet for bitter!” (Isa. 5:20)
People loved the darkness rather than the light
“And this is the judgment: the light has come into the world, and people loved the darkness rather than the light because their works were evil.” (John 3:19 ESV)
What fellowship has light with darkness?
“Do not be bound together with unbelievers; for what partnership have righteousness and lawlessness, or what fellowship has light with darkness?” ( 2 Cor. 6:14)
“Whoever says he is in the light and hates his brother is still in darkness. Whoever loves his brother abides in the light, and in him there is no cause for stumbling. But whoever hates his brother is in the darkness and walks in the darkness, and does not know where he is going, because the darkness has blinded his eyes.” (1 John 2:9-11ESV)
Therefore…
“This is the message we have heard from him and proclaim to you, that God is light, and in him is no darkness at all. If we say we have fellowship with him while we walk in darkness, we lie and do not practice the truth. But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus his Son cleanses us from all sin.” (1 John 1:5-7 ESV)