2 Corinthians 4:1-4 Therefore seeing we have this ministry, as we have received mercy, we faint not;
2 But have renounced the hidden things of dishonesty, not walking in craftiness, nor handling the word of God deceitfully; but by manifestation of the truth commending ourselves to every man’s conscience in the sight of God.
3 But if our gospel be hid, it is hid to them that are lost:
4 In whom the god of this world hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them.
Blindness:
There are several kinds of blindness – legally blind, partially blinded, snow/sun blinded and total blindness. Those who are legally blind can still see forms, figures and object but they do not have enough sight to function normally in everyday events. Those partially blind may be blinded in one eye and still be legally able to drive or function in everyday events. Snow or sun blindness happens when someone is exposed to bright sun light or sunlight in snow and has temporarily lost the ability to see when coming inside or perhaps for a time they experience the inability to see clearly. Total blindness occurs when someone has lost complete sight and is unable to see at all.
Scripture speaks of spiritual blindness to some in differing situations. Our text tells of those who are lost and have been blinded by the enemy which prevents them from coming to Christ for salvation. This is in connection with Jesus’ parable of the Sower and Seed in Matt 13 where Jesus says that the hard soil rejects the word and the enemy steals it before it can take root .The Psalmist tells us that the entrance of God’s word give us light (Psa 119:130, 105; Prov 6:23). When anyone rejected or refuses to accept the light of God’s word, the enemy is enabled to steal it away from them, thus causing blindness. God attempts to shine the light in our hearts but we still retain our own volition over what we believe (2 Cor 4:6).
Israel is blinded in part because of their refusal to accept that Christ was/is their Messiah (2 Cor 3:12-16). They told Pilate we have no king but Caesar and thus gave their light away. At one point Paul told them that he was going to the Gentiles since they (the Jews) rejected the truth about Christ (Acts 13:46).
Darkened understanding:
Paul warns the Christians at Ephesus to be careful not to take too lightly God’s word and to think deeply upon it as it is preached/taught (Eph 4:17-19). He tells them that the reason some do not understand is that they have become apathetic (past feeling), they are indifferent to the Scripture and the light God gives us thru the word. Because of this he says they pursue lust upon lust and seek pleasure over spirituality.