World Wide Study Bible
a Bible passage
The Old Life and the New
17 Now this I affirm and insist on in the Lord: you must no longer live as the Gentiles live, in the futility of their minds.
17. therefore—resuming the exhortation which he had begun with, "I therefore beseech you that ye walk worthy," &c. (Eph 4:1).
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).