"If thine eye be evil, thy whole body shall be full of darkness. If therefore the light that is in thee be darkness, how great is that darkness!" (Matthew 6:23). Scripture makes it plain that hidden sins are "works of darkness." We know from God's Word that light has no communion with darkness.

Peter tells us Christ "preached unto the spirits in prison; which sometime were disobedient" (1 Peter 3:19-20). Disobedience cast these souls into a prison of darkness. Likewise today, every willful act of disobedience causes the light of discernment within us to darken. Over time our perception of truth becomes distorted, and our "open heaven" grows clouded.

The Lord suffers greatly whenever hidden sin brings gross darkness upon our souls. And nothing grieves Him more than when we resist and reject His warnings and convictions. Consider this tragic case described in a letter we received:

"My husband has given himself over completely to Internet pornography. Now I've filed for divorce, and he doesn't even care. We were happily married for twenty-five years before all this happened. I couldn't understand why he spent so much time shut up in his room with his computer. Then one day I walked in and was shocked by the ugly filth I saw on the screen.

"He became obsessed. His personality changed, and a meanness came over him. I knew he was addicted. He said, 'I can't help it. I'm going to do as I please.'"

The apostle Paul directs a horrifying statement to those who walk "in the vanity of their mind" (Ephesians 4:17). Such people justify their sin, no longer seeking deliverance from it. Paul says of them: "Having the understanding darkened, being alienated from the life of God through the ignorance that is in them, because of the blindness of their heart" (verse 18).

How did they become so dark and blinded? They fell under a blindness that comes upon all who give themselves over to sin: "Who being past feeling have given themselves over unto lasciviousness, to work all uncleanness with greediness" (verse 19).

John Owen, the Puritan writer, spells out the tragic result: "A man under the power of some predominant lust is under false security and does not discern coming perilous times."