By nature we are darkened in our understandings and separated from the life of God because of the ignorance that is in us due to the hardening of our hearts. Ephesians 4:18

The things that come from the Spirit of God are foolishness to the man without the Spirit, and, if left to ourselves, we cannot understand them, because they are spiritually discerned. 1 Corinthians 2:14

We are skilled in doing evil; we know not how to do good. Jeremiah 4:22 We know nothing, we understand nothing; we walk about in darkness. Psalm 82:5

God speaks – now one way, now another – though we do not perceive it. Job 33:14 We are ever hearing but never understanding; Matthew 13:14 and we see people, yet they look like trees walking around. Mark 8:24