That is, Satan. Paul here explains why the glorious gospel is veiled to many men. Satan is a personal being (see on Matt. 4:1), and it is imperative that we recognize him when he comes in any form or through any medium. The title “god of this world” alludes to Satan’s attempt to usurp God’s sovereignty over this world. The devil claims to be the god of this world (Matt. 4:8, 9; 1 John 5:19). He has been the invisible ruler of many of the great kingdoms and empires of earth. He is called “the god of this world” because it is his purpose to secure complete control of this world and its inhabitants. He is “the god of this world” because the world is largely under his control. He rules in the hearts of most of its inhabitants (cf. Eph. 2:1, 2). The world obeys his dictates, yields to his temptations, takes part in his wicked ways and abominations. He is the author and instigator of all sin, and the very embodiment of it. Willful sinners are said to be given over to Satan (1 Cor. 5:5; cf. 1 Tim. 1:20). He is the “god of this world” because of his control, even though limited, of the forces of nature, the elements of earth, sea, and sky.

 To speak of Satan as “god of this world” does not mean that God has abdicated sovereignty over the world. Satan’s power and control are strictly limited. He exercises what power he has only by permission of an all-wise God, and only so long as may be necessary for the effective and eternal destruction of sin (1 Cor. 15:24-28; Rev. 12:12).

 Gr. noēmata, “perceptive faculties.” The battle between Christ and Satan is a battle for the minds of men (Rom. 7:23, 25; 12:2; 2 Cor. 3:14; 11:3; Phil. 2:5; 4:7, 8).

Satan’s principal work is to blind or darken men’s minds. He does this by keeping them from the study of God’s Word, by deranging the powers of the mind through excesses of body and soul, by wholly occupying the mind with things of this life, and by appealing to pride and self-exaltation.

 Gr. phōtismos, “enlightenment,” “illumination,” from a verb meaning “to give light,” “to illuminate.” Compare phōs, the usual word for “light” (see on John 1:7, 9).

 Phōtismos is here used of the gospel, which will enlighten every sincere and open mind. Many, nevertheless, remain blind, even when the full light of the gospel shines into their darkened minds. They are like men in a dark room who deliberately keep out the light. They keep the light of the gospel from rising and ascending to the zenith of their lives (see Prov. 4:18).

The issue is one between light and darkness. The most that Satan can do is to blind the minds of men. He cannot darken the light of the gospel; but he can envelop human minds in darkness. He can cause a veil to cover their eyes, even though the gospel enlightens others all around them.

 Satan’s kingdom is the kingdom of darkness (see Isa. 60:2; Matt. 8:12; Luke 22:53; 2 Peter 2:4; Jude 6; Rev. 16:10), and it is for this reason that the devil hates the light of the gospel. He is willing that the light of any substitute for the gospel should shine—the light of knowledge, of culture, of morality, of education, of wealth, and of human wisdom. But his whole effort is turned against the spread of the gospel light, which alone can save men (Acts 4:12). The gospel is the only means by which Satan’s diabolical schemes and deceptions can be exposed, and by which men can see the way from darkness to light. See on John 1:4, 5, 9, 14.

 Gr. eikōn, “image,” “figure,” “likeness.” This word is used in the LXX of Gen. 1:26, and also in 1 Cor. 11:7; Col. 1:15; 3:10; Heb. 10:1. Christ is the express image of the Father, in that the character, attributes, and perfection of both are the same. God the Father is like Jesus (John 12:45; 14:9; Phil. 2:6). Adam and Eve were originally made in that image, and it is the objective of the plan of salvation to restore that image in mankind.

Paul here refers to the penetration of the human soul by the light of the saving knowledge of the gospel.

 The responsibility for spiritual blindness rests not only with Satan but also with those who choose to “believe not.” They have been brought to the light of God’s truth, yet their mental and spiritual reactions are blind and negative. The great fundamental doctrines of the Christian faith appear to them to have no value. But they themselves are responsible, for they have knowingly turned away from the truth. They have eyes but see not (Isa. 6:9; Matt. 13:14, 15; John 12:40; Rom. 11:8-10). They see no beauty in the Lord’s Servant, that they should desire Him (Isa. 53:2).