Transformation through God's Word

a heavily heated argument in evangelism is whether God really provides "all people" the opportunity to come to him or not. Paul in 2 Cor 4:3-4 says

"and even if our gospel is veiled, it is veiled to those who are perishing, in whose case the god of this world has blinded the minds of the unbelieving so that they might not see the light of the gospel of the glory of Christ, who is the image of God."

this implies that though God allows the veiling, it is Satan who actually does the veiling.