Ephesians 4:17-19

As other Gentiles walk. He means those who had not yet been converted to Christ. But, at the same time, he reminds the Ephesians how necessary it was that they should repent, since by nature they resembled lost and condemned men. The miserable and shocking condition of other nations is held out as the motive to a change of disposition. He asserts that believers differ from unbelievers; and points out, as we shall see, the causes of this difference. With regard to the former, he accuses their mind of vanity: and let us remember, that he speaks generally of all who have not been renewed by the Spirit of Christ.

In the vanity of their mind. Now, the mind holds the highest rank in the human constitution, is the seat of reason, presides over the will, and restrains sinful desires; so that our theologians of the Sorbonne are in the habit of calling her the Queen. But, Paul makes the mind to consist of nothing else than vanity; and, as if he had not expressed his meaning strongly enough, he gives no better title to her daughter, the understanding. Such is my interpretation of the word διανοία; for, though it signifies the thought, yet, as it is in the singular number, it refers to the thinking faculty. Plato, about the close of his Sixth Book on a Republic, assigns to διανοία an intermediate place between νόησις and πίστις but his observations are so entirely confined to geometrical subjects, as not to admit of application to this passage. Having formerly asserted that men see nothing, Paul now adds, that they are blind in reasoning, even on the most important subjects.

Let men now go and be proud of free-will, whose guidance is here marked by so deep disgrace. But experience, we shall be told, is openly at variance with this opinion; for men are not so blind as to be incapable of seeing anything, nor so vain as to be incapable of forming any judgment. I answer, with respect to the kingdom of God, and all that relates to the spiritual life, the light of human reason differs little from darkness; for, before it has pointed out the road, it is extinguished; and its power of perception is little else than blindness, for ere it has reached the fruit, it is gone. The true principles held by the human mind resemble sparks; but these are choked by the depravity of our nature, before they have been applied to their proper use. All men know, for instance, that there is a God, and that it is our duty to worship him; but such is the power of sin and ignorance, that from this confused knowledge we pass all at once to an idol, and worship it in the place of God. And even in the worship of God, it leads to great errors, particularly in the first table of the law.

As to the second objection, our judgment does indeed agree with the law of God in regard to the mere outward actions; but sinful desire, which is the source of everything evil, escapes our notice. Besides, Paul does not speak merely of the natural blindness which we brought with us from the womb, but refers also to a still grosser blindness, by which, as we shall afterwards see, God punishes former transgressions. We conclude with observing, that the reason and understanding which men naturally possess, make them in the sight of God without excuse; but, so long as they allow themselves to live according to their natural disposition, they can only wander, and fall, and stumble in their purposes and actions. Hence it appears in what estimation and value false worship must appear in the sight of God, when it proceeds from the gulf of vanity and the maze of ignorance.