Charles Hodge on Ephesians 4:19

V. 19. Who, not the simple relative, but οἵτινες, such as who. The practical proof of their being in the state described is to be found in the fact that being without feeling they give themselves over to the sins mentioned. Ἀπηλγηκότες, no longer susceptible of pain. Conscience ceases to upbraid or to restrain them. They, therefore, give themselves up to excess, to practise all kinds of uncleanness, ἐν πλεονεξίᾳ, with greediness, i. e. insatiably. The parallel passage, 2 Pet. 2, 14, "Having eyes full of adultery, and that cannot cease from sin," would favour this interpretation so far as the idea is concerned. But the word πλεονεξία always elsewhere means, covetousness; a desire to have more. And as this gives a good sense it is not right to depart from the established meaning. Ἐν πλεονεξίᾳ, therefore, means with, i. e. together with, covetousness. The heathen give themselves up to uncleanness and covetousness. These two vices are elsewhere thus associated, as in ch. 5, 3. 5, "Let not uncleanness or covetousness be named among you." "No unclean person, nor covetous man, &c." See also Col. 3, 5. Rom. 1, 29. 1 Cor. 5, 10. Here as in Rom. 1, 24, immorality is connected with impiety as its inevitable consequence. Men in their folly think that morality may be preserved without religion, and even that morality is religion; but reason, experience and Scripture all prove that if men do not love and fear God they give themselves up to vice in some form, and commonly either to uncleanness or avarice. There is a two-fold reason for this; one is the nature of the soul which has no independent source of goodness in itself, so that if it turns from God it sinks into pollution, and the other is the punitive justice of God. He abandons those who abandon him. In Rom. 1, 24 and elsewhere, it is said ‘God gives the impious up to uncleanness;’ here it is said, they give themselves up. These are only different forms of the same truth. Men are restrained from evil by the hand of God, if he relaxes his hold they rush spontaneously to destruction. All systems of education, all projects of reform in social or political life, not founded in religion, are, according to the doctrine of this passage and of all Scripture, sure to lead to destruction.