Answer
Ephesians 5:8 describes followers of Christ and exhorts them: “You are light in the Lord. Live as children of light.” From the beginning, the Bible develops and explores the theme of moral dualism, or “good versus evil,” using the contrasting elements of light and darkness. God created light from darkness (Genesis 1:2–3). His presence, goodness, and life are represented as light, whereas His absence, evil, and death are pictured as darkness (see Job 33:28; Psalm 56:13; cf. Job 18:5; Psalm 49:18–19; Jeremiah 13:16). In the New Testament, the symbolism of light focuses sharply on Jesus Christ as Messiah and incarnate revelation of God.
The Gospel writers cited Old Testament Scripture to declare that Jesus Christ’s arrival brought the presence of God to earth: “The people who sat in darkness have seen a great light. And for those who lived in the land where death casts its shadow, a light has shined” (Matthew 4:16, NLT; see also Luke 1:79; Luke 2:32; cf. Psalm 23:4; 107:10; Isaiah 9:2; 42:7). John’s Gospel offers the most thorough development of the light and darkness theme. Jesus is the Light that “shines in the darkness, and the darkness can never extinguish it” (John 1:5, NLT). Jesus presented Himself as “the light of the world. Whoever follows me will never walk in darkness, but will have the light of life” (John 8:12).
Naturally, God’s children—those who belong to Jesus Christ—would be called people of light. The apostle Paul told the Ephesian Christians not to behave like the unsaved people of the world: “For you were once darkness, but now you are light in the Lord. Live as children of light (for the fruit of the light consists in all goodness, righteousness and truth) and find out what pleases the Lord” (Ephesians 5:8–10). Since “God is light” and “in him there is no darkness at all” (1 John 1:5), God’s children are meant to be “light in the Lord.” Believers are to “take no part in the worthless deeds of evil and darkness” but instead, “expose them . . . for the light makes everything visible” (Ephesians 5:11–14), NLT).
The “real life” of every Christian is said to be “hidden with Christ in God” (Colossians 3:3, NLT; see also Ephesians 2:13). Jesus is our life (Colossians 3:4), our light, and our salvation (Psalm 27:1). God through Jesus is the source of our light (Psalm 34:5; Isaiah 60:19–20). Therefore, “we walk in the light, as he is in the light” (1 John 1:7, ESV).
Light represents the righteousness of God (2 Corinthians 6:14), and therefore, believers are the righteousness of God in Jesus Christ (2 Corinthians 5:21). We are “light in the Lord” to a lost and dying world (Ephesians 5:8). Jesus taught His followers, “You are the light of the world. A town built on a hill cannot be hidden. Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house. In the same way, let your light shine before others, that they may see your good deeds and glorify your Father in heaven” (Matthew 5:14–16). As lighthouses pointing the way to the Father and beacons of His truth, we must be careful to “live clean, innocent lives as children of God, shining like bright lights in a world full of crooked and perverse people” (Philippians 2:15, NLT).
As Jesus neared the hour of His death, He told His disciples, “My light will shine for you just a little longer. Walk in the light while you can, so the darkness will not overtake you. Those who walk in the darkness cannot see where they are going. Put your trust in the light while there is still time; then you will become children of the light” (John 12:35–36, NLT).
The Lord appointed Paul as a light to the Gentiles: “To open their eyes and turn them from darkness to light, and from the power of Satan to God, so that they may receive forgiveness of sins” (Acts 26:18). Later, Paul wrote, “The night is almost gone; the day of salvation will soon be here. So remove your dark deeds like dirty clothes, and put on the shining armor of right living” (Romans 13:12, NLT). He urged Christians to stay alert: “For you are all children of the light and of the day; we don’t belong to darkness and night. So be on your guard, not asleep like the others” (1 Thessalonians 5:5–6, NLT).
Being light in the Lord means being an imitator of Jesus Christ (1 Corinthians 11:1), following in His footsteps (Hebrews 12:1–2; 1 Peter 2:21), and living in a way that honors, glorifies, and reflects God’s life in everything we do (Ephesians 4:1; 5:2; Colossians 1:10; 3:17 1 Corinthians 10:31; 1 Peter 4:11).
