Paul has been establishing his credibility and sincerity so far in 2 Corinthians
Paul now widens the scope of his argument from specifics about himself, to the general message of the gospel he preaches
The false apostles Paul has been pitted against have not been changed by the power of God (v. 2\)
The message of the gospel is veiled to those who are blind by unbelief and perishing in their sin, while those who would proclaim it truly are those who are changed inwardly (vv. 3-4)