4.3 The word for "hidden" here is "kalypt-oo" as in the opposite of "apocalyse." The hiddenness of the message has always fascinated me; the word hidden is also used in Exodus when Moses goes up Mt. Sinai and the cloud hids the mountain. In this case, the hiddenness seems to protect the people.
4.3 The word here for "perishing" is in the present passive. The word (apollu-mi) means to perish, lose or destroy (if you want to lose your life...Herod sought to destroy the child...) Not only is the word intense, but it is in the present, suggesting that there are people who currently are undergoing this action...consistently. Paul will elsewhere (1 Cor 1:18) suggest this idea, that death and destruction are active forces grinding down people.
4.4 Take a quick look at 2 Cor 3:14 when you read this verse; there Paul takes about the Law covering people's minds. Interesting that the gods of this age then have the same affect as the god of the Old Covenant: They cover the Gospel.
4.6 Not the deepest, but perhaps a sermon nugget none the less: The word for "made to shine" is "lamp-oo."