In whom the god of this world, etc. - We see here that those whose minds are blinded, are they who believe not; and because they believe not, their minds continue in darkness, and are proper subjects for Satan to work on; and he deepens the darkness, and increases the hardness. But who is meant by the god of this world? It is generally answered, the same who is called the prince of this world, John 16:11. But the question recurs, who is the prince of this world? and the answer to both is, Satan. The reader will do well to consult the notes on John 12:31, and the concluding observations on John 14:30. I must own I feel considerable reluctance to assign the epithet ὁ Θεος, The God, to Satan; and were there not a rooted prejudice in favor of the common opinion, the contrary might be well vindicated, viz. that by the God of this world the supreme Being is meant, who in his judgment gave over the minds of the unbelieving Jews to spiritual darkness, so that destruction came upon them to the uttermost. Satan, it is true, has said that the kingdoms of the world and their glory are his, and that he gives them to whomsoever he will; Matthew 4:8, Matthew 4:9. But has God ever said so? and are we to take this assertion of the boasting devil and father of lies for truth? Certainly not. We are not willing to attribute the blinding of men's minds to God, because we sometimes forget that he is the God of justice, and may in judgment remove mercies from those that abuse them; but this is repeatedly attributed to him in the Bible, and the expression before us is quite a parallel to the following, Isaiah 6:9; : Go and tell this people, Hear ye indeed, but understand not; and see ye indeed, but perceive not. Make the Heart of this People Fat, and Make their Ears Heavy, and Shut their Eyes; Lest they see with their eyes, and hear with their ears, and understand with their heart, etc. And see the parallel places, Matthew 13:14, Matthew 13:15; Mark 4:12; John 12:40; and particularly Romans 11:8-10; : God Hath Given Them the Spirit of Slumber, Eyes that they Should not See, and Ears that they Should not Hear; let their Eyes be Darkened, etc. Now all this is spoken of the same people, in the same circumstances of wilful rebellion and obstinate unbelief; and the great God of heaven and earth is he who judicially blinds their eyes; makes their hearts fat, i.e. stupid; gives them the spirit of slumber: and bows down their back, etc. On these very grounds it is exceedingly likely that the apostle means the true God by the words the god of this world.
And as to the expression this world, αιωνος τουτου, we are not to imagine that it necessarily means wicked men, or a wicked age; for it is frequently used to express the whole mundane system, and all that is called time: Whosoever speaketh against the Holy Ghost, it shall not be forgiven him, neither εν τουτῳ τῳ αιωνι, in This World, nor in the world to come; Matthew 12:32. In Luke 20:34, the children, υἱοι του αιωνος τουτου, of This World, mean simply mankind at large in their state of probation in this lower world, in opposition to their state in the world to come. The same meaning the word has in several other places, to which l need not refer; it simply implying the present state of things, governed by the Divine providence, in contradistinction from the eternal state: and it is very remarkable that, in 1 Timothy 1:17, God himself is called Βασιλευς των αιωνων, the King of the World; what we call King eternal; but here it evidently means him who governs both worlds, and rules in time and eternity. This character among the Asiatics is considered essential to God; and therefore in the very first surat of the Koran he is called Rubbi Alalameen, "the Lord of both worlds," an expression perfectly similar to that above. But it is needless to multiply examples; they exist in abundance. Some, and particularly the ancient fathers, have connected του αιωνος τουτου with των απιστων, and have read the verse: But God hath blinded the minds of the unbelievers of this world, etc. Irenaeus, Tertullian, Chrysostom, Theodoret, Photius, Theophylact, and Augustine, all plead for the above meaning; and St. Augustine says that it was the opinion of almost all the ancients.
Lest the light of the glorious Gospel - They have resisted the grace which God gave them, and have refused to yield to the evidences which amply prove the Messiahship of Jesus; and therefore their eyes were judicially darkened, as it is said in the prophet: He hath closed their eyes, and hath given them the spirit of slumber. That is, they have shut their eyes against the light, and their blindness and stupor are the consequence.
By glorious Gospel we are to understand the luminous Gospel; that which comes with so much light and evidence to every candid mind.
Who is the image of God - Christ is called, Hebrews 1:3, the brightness of God's glory, and the express image of his person. See the note at Hebrews 1:3.