Ephesians 5:8
8. sometimes—"once." The emphasis is on "were." Ye ought to have no fellowship with sin, which is darkness, for your state as darkness is now PAST. Stronger than "in darkness" (Ro 2:19).
light—not merely "enlightened"; but light enlightening others (Eph 5:13). in—in union with the Lord, who is THE LIGHT. children of light—not merely "of the light"; just as "children of disobedience" is used on the opposite side; those whose distinguishing characteristic is light. PLINY, a heathen writing to Trajan, bears unwilling testimony to the extraordinary purity of Christians' lives, contrasted with the people around them. Ephesians 5:11
11. unfruitful works of darkness—Sins are terminated in themselves, and therefore are called "works," not "fruits" (Ga 5:19, 22). Their only fruit is that which is not in a true sense fruit (De 32:32), namely, "death" (Ro 6:21; Ga 6:8). Plants cannot bear "fruit" in the absence of light. Sin is "darkness," and its parent is the prince of darkness (Eph 6:12). Graces, on the other hand, as flourishing in "the light," are reproductive, and abound in fruits; which, as harmoniously combining in one whole, are termed (in the singular) "the FRUIT of the Spirit" (Eph 5:9).
rather, &c.—Translate as Greek, "rather even reprove them" (compare Mt 5:14-16). Not only "have no fellowship, but even reprove them," namely, in words, and in your deeds, which, shining with "the light," virtually reprove all that is contrary to light (Eph 5:13; Joh 3:19-21). "Have no fellowship," does not imply that we can avoid all intercourse (1Co 5:10), but "avoid such fellowship as will defile yourselves"; just as light, though it touch filth, is not soiled by it; nay, as light detects it, so, "even reprove sin." Ephesians 5:13
13. that are reproved—rather, "when they are reproved," namely, by you (Eph 5:11).
whatsoever doth make manifest—rather, "everything that is (that is, suffers itself to be) made manifest (or 'shone upon,' namely, by your 'reproving,' Eph 5:11) is (thenceforth no longer 'darkness,' Eph 5:8, but) light." The devil and the wicked will not suffer themselves to be made manifest by the light, but love darkness, though outwardly the light shines round them. Therefore, "light" has no transforming effect on them, so that they do not become light (Joh 3:19, 20). But, says the apostle, you being now light yourselves (Eph 5:8), by bringing to light through reproof those who are in darkness, will convert them to light. Your consistent lives and faithful reproofs will be your "armor of light" (Ro 13:12) in making an inroad on the kingdom of darkness.