Light is crucial for making your way in darkness. In Ephesians 5:8–14. Paul points you to the true light.
Be the light that you are. You were darkness. The light of God’s grace shows most clearly when it is contrasted with the darkness which we once were. Paul repeats the point made in Ephesians 2, that we were dead in sin, blind, unable to remedy the situation. Note the strong language—not that you were in darkness, not that your eyes were dim, but that you were darkness.
But now, because you are light, walk as children of light. Now you are light in the Lord. The One who is the Light of the world has shined into your life, and you, in turn, become a light bearer. You are a lamp on a lampstand. Moses on Mt. Sinai stood in the presence of God until his face shone. You have the glory of the risen Lord permeating your life. You are characterized by light. Because of what you are, walk that way. Walk as children of light. Bear the fruit of goodness, righteousness, and truth. Understand God, soak yourself in his Word, and learn what pleases him.
As you do, expose the deeds of darkness. Shun sin. Sin is fruitless. Notice that the contrast with fruit is works, deeds of darkness. Efforts at self-salvation only serve to churn you deeper into the mire. Don’t even speak about the depths of sin. Sin is a contradiction of what you are in Christ. Salvation by faith alone, by grace alone (both absolutely true) leaves no room for complacency, or for tolerating or minimizing sin.
“Beware at all costs that you do not thrust the grace that is given you under foot, or make it without avail to you. For his calling of you to the knowledge of our Lord Jesus Christ was in order that you should be wholly changed, and should show that it is not in vain that God has called you.”
John Calvin, Sermons on Ephesians, on Ephesians 5:8–11
As you focus on the light, expose the darkness by walking in the light. Sin has to be exposed–but not by digging into it. Rather, expose sin by simply doing what is right. Is Paul reflecting on his past, on the shining influence of Stephen, who was apparently a member of the same synagogue in Jerusalem, Acts 6? Did the light of Stephen’s life and words burn into the conscience of Saul of Tarsus (who may be Luke’s source for the details of how Stephen looked and what he said during his martyrdom). Ironically for Saul/Paul, it was blinding heavenly light that burned away the darkness of his soul.
Paul is not just reflecting on his past—he is concerned with how you live. Christ will shine on you. Rise—because you have been raised in Christ. Verse 14b is a quote, introduced by “it is said.” But it is either a paraphrase, or perhaps an early hymn. In any case it looks back to Isaiah 60:1. Paul makes explicit what that messianic passage implies, that the glorious light that shines in that Old Testament prophecy is ultimately the light of the incarnate Christ. You have been raised and will be raised in Christ. And you must live as one who has been raised.
“By faith Christ or his Spirit is the author and origin of a new life in those who are called (Gal. 3:2; 4:6) so that now they are very different, new, and spiritual people. The old has gone; all things have become new (2 Cor. 5:17). they have passed from death into life (Eph. 2:5; 5:14; Col. 3:1). They have been crucified to the flesh and to the world (Gal. 5:24; 6:14). They themselves no longer live, but Christ lives in them (Gal. 2:20).”
Herman Bavinck, Reformed Dogmatics, Vol. 4, page 50
The glory of God shines on you in the risen Lord. Don’t be afraid to stick out. You will be noticed if the light of God shines out from you. Be sure that it is the glory of God shining, and not simply your being noticed because of the harsh way you come across. Look for the light’s fruits of goodness, righteousness, and truth in your life. Your resurrection is inextricably connected with that of Christ. You have been raised with him, and seated in the heavenlies. How can you continue in darkness?
Be the light that you are in Christ, the risen Lord.