Jamieson, Fausset and Brown on Ephesians 5:9

9. fruit of the Spirit--taken by transcribers from Ga 5:22. The true reading is that of the oldest manuscripts, "The fruit of THE LIGHT"; in contrast with "the unfruitful works of darkness" (Ep 5:11). This verse is parenthetic. Walk as children of light, that is, in all good works and words, "FOR the fruit of the light is [borne] in [Alford; but Bengel, 'consists in'] all goodness [opposed to 'malice,' Ep 4:31], righteousness [opposed to 'covetousness,' Ep 5:3] and truth [opposed to 'lying,' Ep 4:25]."