This I say therefore, and testify in the Lord - I bear witness in the name of the Lord Jesus, or ministering by his authority. The object of this is, to exhort them to walk worthy of their high calling, and to adorn the doctrine of the Saviour. With this view, he reminds them of what they were before they were converted, and of the manner in which the pagan around them lived.

That ye henceforth walk not - That you do not henceforth live - the Christian life being often in the Scriptures compared to a journey.

As other Gentiles walk - This shows that probably the mass of converts in the church at Ephesus were from among the pagan, and Paul regarded them as Gentile converts. Or it may be that he here addressed himself more particularly to that portion of the church, as especially needing his admonition and care.

In the vanity of their mind - In the way of folly, or in mental folly. What he means by this he specifies in the following verses. The word "vanity" in the Scriptures means more than mere "emptiness." It denotes moral wrong, being applied usually to those who worshipped vain idols, and then those who were alienated from the "true" God.

Walk not as other Gentiles walk - Ye are called to holiness by the Gospel, the other Gentiles have no such calling; walk not as they walk. In this and the two following verses the apostle gives a most awful account of the conduct of the heathens who were without the knowledge of the true God. I shall note the particulars.

1. They walked in the vanity of their mind, εν ματαιοτητι του νοος αὑτων· In the foolishness of their mind; want of genuine wisdom is that to which the apostle refers, and it was through this that the Gentiles became addicted to every species of idolatry; and they fondly imagined that they could obtain help from gods which were the work of their own hands! Here their foolishness was manifested.

This I say therefore and testify in the Lord,.... These words may be considered either as an assertion, and so a testimonial of the different walk and conversation of the saints at Ephesus, from the rest of the Gentiles; or as an exhortation in the name of the Lord to such a walk, the apostle here returning to what he stirs them up to in Ephesians 4:1

that ye henceforth walk not as other Gentiles walk, in the vanity of their mind; every natural man walks in a vain show; the mind of man is vain, and whoever walk according to the dictates of it, must walk vainly: the phrase is expressive of the emptiness of the mind; it being naturally destitute of God, of the knowledge, fear, and grace of God; and of Jesus Christ, of the knowledge of him, faith in him, and love to him; and of the Spirit and his graces; and it also points at the instability and changeableness of the human mind, in which sense man at his best estate was altogether vanity; as also the folly, falsehood, and wickedness of it in his fallen state: and the mind discovers its vanity in its thoughts and imaginations, which are vain and foolish; in the happiness it proposes to itself, which lies in vain things, as worldly riches, honours, &c. and in the ways and means it takes to obtain it, and in words and actions; and the Gentiles showed the vanity of their minds in their vain philosophy and curious inquiries into things, and in their polytheism and idolatry: to walk herein, is to act according to the dictates of a vain and carnal mind; and it denotes a continued series of sinning, or a vain conversation maintained, a progress and obstinate persisting therein with pleasure: now God's elect before conversion walked as others do, but when they are converted their walk and conversation is not, at least it ought not to be, like that of others: the Alexandrian copy, and some others, the Vulgate Latin and Ethiopic versions, leave out the word "other", and only read, "as the Gentiles", &c.

This - therefore

Referring to what follows. Therefore, resuming the exhortation of Ephesians 4:1-3.

Testify

Solemnly declare. Compare Acts 20:26; Galatians 5:3.

Other Gentiles

Omit other.

Vanity of their mind (ματαιότητι τοῦ νοὸς αὐτῶν)

For vanity see on Romans 1:21; see on Romans 8:20. For mind, see on Romans 7:23.

{12} This I say therefore, and testify in the Lord, that ye henceforth walk not as other Gentiles walk, in the {z} vanity of their mind,

(12) He descends to the fruits of Christian doctrine, and reasons first upon the principles of conduct and actions, setting down a most grave comparison between the children of God, and those who are not regenerated. For in these men all the powers of the mind are corrupted, and their mind is given to vanity, and their senses are darkened with most gross mistiness, and their affections are so accustomed by little and little to wickedness, that at length they run headlong into all uncleanness, being utterly destitute of all judgment.

(z) If the noblest parts of the soul are corrupted, what is man but solely corruption?

4:17 This I say, therefore. Now, after the statement of the great principles named in Eph 4:3-16, Paul returns to the exhortation of Eph 4:1-3.

Walk not as other Gentiles. Having come out from the heathen and abandoned all their sins.

The vanity of their mind. Vanity of mind means what is a waste of life.

4:17 This therefore I say - He returns thither where he begun, Eph 4:1. And testify in the Lord - In the name and by the authority of the Lord Jesus. In the vanity of their mind - Having lost the knowledge of the true God, Rom 1:21. This is the root of all evil walking.

17. therefore-resuming the exhortation which he had begun with, "I therefore beseech you that ye walk worthy," &c. (Eph 4:1).

testify in the Lord-in whom (as our element) we do all things pertaining to the ministry (1Th 4:1 [Alford]; Ro 9:1).

henceforth . not-Greek, "no longer"; resumed from Eph 4:14.

other-Greek, "the rest of the Gentiles."

in the vanity, &c.-as their element: opposed to "in the Lord." "Vanity of mind" is the waste of the rational powers on worthless objects, of which idolatry is one of the more glaring instances. The root of it is departure from the knowledge of the true God (Eph 4:18, 19; Ro 1:21; 1Th 4:5).

4:17-24 The apostle charged the Ephesians in the name and by the authority of the Lord Jesus, that having professed the gospel, they should not be as the unconverted Gentiles, who walked in vain fancies and carnal affections. Do not men, on every side, walk in the vanity of their minds? Must not we then urge the distinction between real and nominal Christians? They were void of all saving knowledge; they sat in darkness, and loved it rather than light. They had a dislike and hatred to a life of holiness, which is not only the way of life God requires and approves, and by which we live to him, but which has some likeness to God himself in his purity, righteousness, truth, and goodness. The truth of Christ appears in its beauty and power, when it appears as in Jesus. The corrupt nature is called a man; like the human body, it is of divers parts, supporting and strengthening one another. Sinful desires are deceitful lusts; they promise men happiness, but render them more miserable; and bring them to destruction, if not subdued and mortified. These therefore must be put off, as an old garment, a filthy garment; they must be subdued and mortified. But it is not enough to shake off corrupt principles; we must have gracious ones. By the new man, is meant the new nature, the new creature, directed by a new principle, even regenerating grace, enabling a man to lead a new life of righteousness and holiness. This is created, or brought forth by God's almighty power.