When men choose to reject the truth, God tends to withhold further truth from them. The result is spiritual and intellectual darkness.
Most men would rather accept lies than to believe the truth. This bias against the truth has been present as far back as the garden of Eden.
Man has ignored, rejected, and despised the truth on every front. Yet, God, in His faithfulness, continues to show His truth to every generation.
Men could know the truth if they desired to know it. Sadly, most men refuse to pursue and know the truth made so readily available unto them.
