What does Ephesians 5:8 mean?
Paul contrasts the past of his readers with their current status. Before knowing Christ, all human beings are in "darkness." As believers, they are instead "light in the Lord." The contrast of dark/light is as old as Genesis 1 and is commonly associated with evil versus good, exactly as Paul uses it in this context.Based on their new status, Paul commands his readers to, "Walk as children of light." Paul uses this phrase in one other passage, 1 Thessalonians 5:5, where he describes Christians as "children of light, children of the day. We are not of the night or of the darkness." In that passage, the emphasis is on living "awake," being alert to obey the Lord. This is a theme Paul will again note in Ephesians 5:14. Paul's similar application here is to live in obedience as believers. Christians are to imitate God (Ephesians 5:1), walk in love (Ephesians 5:2), and flee from sinful actions (Ephesians 5:3–6). They should not live like unbelievers or be "partners" with them (Ephesians 5:7).
Ephesians 5:1–21 continues Paul's invaluable instructions on how Christians should live out their faith. Rather than imitating the world, or being controlled by worldly things, Christians are to be filled with the Spirit. Specific flaws such as sexual immorality, crude speech, and wasting of time are discouraged. Instead, believers ought to submit to one another out of respect for Christ, providing a powerful witness to the world.
Chapter 5 begins with an admonition to imitate Christ. In order to do so, Christians must avoid sexual immorality, vulgar language, foolishness, and other inappropriate attitudes. Paul warns that those who persist in these behaviors are not part of the kingdom of God. The passage then transitions to an explanation of mutual submission, including that between husbands and wives. Wives are to submit to their husbands, and respect them. Husbands are to love their wives in a Christ-like, sacrificial, and humble way.