Sin is not shallow. It runs to the bone and settles into the assumptions we carry without noticing. Its danger lies in its invisibility; it hides under the skin and rarely announces itself with a warning label. Over time it also bends our vision, so even honest self-examination feels like looking through fog. Paul told the Corinthians that “the god of this world has blinded the minds of the unbelievers” so that truth could stand plainly before them and still not be grasped (Second Corinthians 4:4). Jeremiah faced that same blindness in Israel. After comparing them to an adulterer, a corrupt branch, and an unremovable stain, he exposes their denial: “How can you say, ‘I am not unclean, I have not gone after the Baals’? Look at your way in the valley; know what you have done” (Jeremiah 2:23). The problem was not a lack of evidence but a lack of sight.
Commentators help us see how deep the blindness ran. Dearman locates the “valley” as Hinnom, infamous for idolatry and child sacrifice. Davidson observes that addiction to evil reshapes values until nothing seems wrong. Mackay adds that the people defended themselves with appeals to orthodoxy, the temple, and functioning religious systems. In other words, the checklist looked impressive while the heart wandered freely. That feels uncomfortably familiar. It is easy to confuse activity with faithfulness and to assume that correct forms guarantee a clean conscience. Jeremiah insists otherwise. Their practices differed little from the pagans around them, even though they wore better vocabulary and stood closer to holy furniture.
Jeremiah presses them to “know” what they had done, not as new information but as honest assessment under the covenant. Mackay notes that facts were available; discernment was missing. I remember my wife’s years at Assure Women’s Center and a young woman convinced she needed an abortion to fit into a prom dress. She spoke confidently about unborn souls floating in never-never land, waiting for assignment. The logic was creative, if nothing else. Jeremiah had already answered such thinking: God says, “Before I formed you in the womb I knew you” (Jeremiah 1:5). The New Testament sharpens the light. Jesus declares, “Everyone who practices sin is a slave to sin” (John 8:34), and Paul reminds us that self-deception is a skill easily learned (Galatians 6:3). Christ does not merely expose blindness; He heals it. As Paul writes, “God… has shone in our hearts to give the light of the knowledge of the glory of God in the face of Jesus Christ” (Second Corinthians 4:6). That light is steady, revealing what we might otherwise rationalize away.