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Who are you? And being who you are, what difference does it make in the way you live? Those are the two questions that our passage addresses.


Paul has ascribed different terms for the identity of the Christian believers. They are “saints”; they are “members of the household of God” (2:19); God’s “workmanship, created in Christ Jesus for good works” (2:10); together, they are “a dwelling place for God by the Spirit” (2:22); they are “fellow heirs, members of the same body, and partakers of the promise in Christ Jesus through the gospel” (3:6); they are “beloved children” of God (5:1). These perspectives are in contrast to what they once were: “sons of disobedience” (2:2); “children of wrath” (2:3); “strangers to the covenants of promise (2:12); “strangers and aliens” (2:19).

Verse 8 presents the direct contrast of “once were” and “now are”: “for at one time you were darkness, but now you are light in the Lord.” Let’s take time to consider of how light and darkness are used in Scripture.

The first recorded words of God in Scripture are in Genesis 1:3. “Darkness was over the face of the deep…And God said, ‘Let there be light.’” Darkness is associated with lifelessness; light is connected with life. Reading through the psalms, to be the beneficiary of God’s light is to receive his favor, to be guided by him, to be illumined, to be saved. Isaiah looks to the Great Light that will come to God’s people, a time when God himself will be their light and glory.

The gospels record the coming of that light. Matthew says that Jesus is the light spoken of by Isaiah. Luke records how he is the one who gives light to those dwelling in darkness (1:78) and be a light for revelation to the Gentiles and for glory to Israel (2:32).

John is the writer who most fully develops the theme of light and darkness, specifically of Jesus being the light. In his prologue he writes, “in him [Jesus] was life, and the life was the light of men. The light shines in the darkness, and the darkness has not overcome it” (1:4-5). He goes on to write in verse 9: “The true light, which enlightens everyone, was coming into the world.”

The true light certainly does enlighten men, but, more to the point in the prologue, it also “sheds light” on every man. This is how the theme of light and darkness is played out in John’s gospel. The light of Jesus brings understanding, but it also reveals the hearts of all men and prove whether they love the light they profess to love or in truth love the darkness which hides the evil within: “And this is the judgment: the light has come into the world, and people loved the darkness rather than the light because their works were evil” (John 3:19).

Jesus spoke of himself as the Light, but he also spoke of his disciples – those who belong to him – as being lights as well.

“You are the light of the world. A city set on a hill cannot be hidden. 15 Nor do people light a lamp and put it under a basket, but on a stand, and it gives light to all in the house. 16 In the same way, let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven” (Matthew 5:14-16).

Paul applied a verse in Isaiah to himself and his fellow apostles that was used of Jesus: “For so the Lord has commanded us, saying,

      ‘I have made you a light for the Gentiles,

             that you may bring salvation to the ends of the earth’ ” (Acts 13:47).

So, there is God creating light; God being light for his people; prophesy of the Light to come among men. Jesus comes in fulfillment of that prophecy. He is the Light who enters into the world through his incarnation. He sheds light that enlightens us about God and truth; he sheds light on our very hearts, revealing who love light and who love darkness. Then he passes on his light to us that we in turn might show the light of God and of the Gospel.

It is in the epistles, the letters to the churches, that the kingdom of darkness versus the kingdom of light is more fully expounded. In 1 John, we are told “that God is light and in him is no darkness at all” (1:5). Therefore we are to walk in light. John’s specific application of walking in light is to love one’s brother. The love for one’s Christian brother or sister is the measure of being in the light. To hate is to be in darkness.

Peter tells the readers of his first letter: “But you are a chosen race, a royal priesthood, a holy nation, a people for his own possession, that you may proclaim the excellencies of him who called you out of darkness into his marvelous light” (1 Peter 2:9).

Paul tells the Christians in Rome to “cast off the works of darkness and put on the armor of light” (13:11). Writing in 2 Corinthians he makes reference to the Genesis passage in showing how light was given to him and his fellow workers: “For God, who said, ‘Let light shine out of darkness,’ has shone in our hearts to give the light of the knowledge of the glory of God in the face of Jesus Christ (2 Corinthians 4:1-6). Writing two chapters later about how believers are not to be unequally yoked with unbelievers he argues, “What fellowship has light with darkness?” (6:14). He echoes Peter in Colossians when he writes, “giving thanks to the Father, who has qualified you to share in the inheritance of the saints in light. 13 He has delivered us from the domain of darkness and transferred us to the kingdom of his beloved Son” (1:12-13). And to the Thessalonians, he calls on them to be alert for Christ’s return: “But you are not in darkness, brothers, for that day to surprise you like a thief. 5 For you are all children of light, children of the day. We are not of the night or of the darkness” (1 Thessalonians 5:4-5).

So the light of God, the light of Christ is the light passed on to us that we are to show forth, indeed, to “shine as lights in the world” (Philippians 2:15). We are to be “as lights.” We have been brought “into” the light which shines “in” our hearts. We are to be light, in that we are to show forth our good works.

Our verse, though, suggests something transformative about light. Note clearly what he says: “for at one time you were darkness, but now you are light in the Lord.” He does not say they were in darkness/are in light, but that they were darkness; they are light.

Living in the darkness, giving in to the darkness infects the soul. Darkness is not merely around you; it is in you. But “in the Lord,” a transformation takes place. When Christ clothes us with his righteousness; when he sends his Spirit to dwell within and to regenerate us, we take on light. We become light. That is now our identity, the essence of our being as saints.

And it is with that understanding in mind that Paul tells the saints to act out what they are: “Walk as children of light.” He has already indentified the saints as “beloved children” (5:1). If they are truly the beloved children of God, who himself is light, then they are children of light. It is in their spiritual genes. They cannot deny their heritage anymore than children can deny their blood heritage of the parents who gave them birth. Therefore, walk accordingly to who they are.

What does that walk look like? This is what Paul has been describing all along under the image of putting off the old self and putting on the new. In verse 9 he sums up the walk in terms of character: “(for the fruit of light is found in all that is good and right and true).” Matthew Henry defines these terms this way: “good” is “an inclination to do good [or benevolence] and to show mercy”; “right” “signifies justice in our dealings”; “truth” is “sincerity and uprightness of heart.”

Together they form a balanced life that allows each trait to be fully realized. Consider “goodness.” It is good to be good, to be a person who does good things for others. Scripture tells us in Galatians 6:9-10 to “Not grow weary of doing good” and, “as we have opportunity, [to] do good to everyone.” And yet in our efforts to do good, we can cut corners on what is right. Many a person with good intentions have caused harm by bending the law or by enabling the person they are supposedly helping to fail to do what is right or good. Goodness must be balanced with justice, with a sense for fair play and doing what is right.

Psalm 15 opens with this question: “O Lord, who shall sojourn in your tent? Who shall dwell on your holy hill?” The answer is “He who walks blamelessly and does what is right.” What is right? It is to obey the commands of God. And so it is good to be a person who strives to be obedient to God’s law and to be concerned with justice and fair play. But then, it is easy in our zeal to be obedient to God’s law that we miss the intent of God’s law – to love God and to love our neighbor. The Pharisees were intent on fulfilling righteousness through obeying God’s law. Jesus said to these “righteous” Pharisees, “Go and learn what this means, ‘I desire mercy, and not sacrifice’” (Matthew 9:13). Both goodness and righteousness need to dwell together.

And for both, there must be “truth.” Jesus told Pilate that he came into the world to bear witness to the truth. Pilate uttered that famous line, “What is truth?” If he had been listening, Jesus had already given the answer: “Everyone who is of the truth listens to my voice.” Jesus is the Truth, and all that he speaks and affirms is true, namely, what is written in Scripture. Many seek to be good and appear to be good, yet they lack truth. They lack a true understanding of Jesus and his work and his commands. Many seek to act righteously and yet lack the same understanding. Without this truth as their foundation, their good and righteous acts are always limited, always slightly skewered, leading others astray from the God of goodness and righteousness. Then further, as Matthew Henry noted, “true” or “truth” refers to the true sincerity and uprightness of heart. Simply put, a person who possesses truth is an honest person, one who is not a hypocrite. His acts of justice and fair play come from a pure heart. Likewise his good works. They stem from a heart that truly does desire the good of others. They are not masking a false heart. Such a person truly loves the truth that is of Jesus Christ, and out of that truth he sincerely strives to do good and to act with justice.

Let’s review. Paul has been telling the saints – i.e. Christian believers – that they are no longer darkness but light. They became light through the work of Christ the Lord and the Spirit whom he has sent. Consequently they are to walk in a manner that shows them to be children of light. That walk bears the fruit of goodness and righteousness and truth, all three of which are needed to be light.

Verse 10 then reads: and try to discern what is pleasing to the Lord. Last week I mentioned being baffled by the way the ESV translated a word in verse 7 – “associate.” I learned subsequently that the new edition had changed it to the more appropriate term “partner.” Again, I am baffled by the translation, and this time the newer edition has not changed it. “Try to discern” is the translation of one Greek term, which could have been simply rendered “discern” without the “try to.” Furthermore, it gives the impression that “try to discern” is in an imperative form just like the verb “walk” in verse 8. But it is not. It is a participle, defining what the walk entails. The result of the ESV translation is that it seems to be saying just what it says – that along with walking as children of light, we are to also try to figure out God’s will while we are at it. “Walk in the way of light, and, oh, also do what you can to discern what really pleases the Lord.”

But Paul has already been teaching what pleases the Lord. That’s what chapter 4 was about and what chapter 5 is about. There are the ways connected with the old self, which do not please the Lord. And there are the ways connected with the new self, which do please him. The King James Version has the best handle on the translation – “Walk as children of light…proving what is acceptable unto the Lord.”

“Proving” may carry two senses, both of which fit in well here. The Christian who walks as a child of light, doing that which is good and right and true, will all the more clearly discern what pleases the Lord in the particulars of his life. He who already does what he knows to be good is likely to discern what is good in any given situation. He who already acts righteously is likely to know what is fair when the next circumstance arises. And he who already adheres to the truth is likely to recognize what is true when the time come. If you want to know what pleases the Lord, then be doing now what Scripture makes clear pleases him.

The other sense, which I think is more to the point here, is proving to others what pleases the Lord. Christians who walk as children of light, who bear the fruit of all that is good and right and true, prove to the world what is pleasing to the Lord. Believers are to be light that shines forth in this dark world what is pleasing to the Lord.


So, how well has your light been shining? To update the metaphor, are all the batteries in your flashlight operating at full capacity? You have three of them – goodness, righteousness, and truth. Now is the time to do battery testing.

Perhaps you have been a good-hearted soul, but doing what is right…that could use some work. Maybe you bend the rules a bit to do what you think is good. Maybe you have doing the right thing down pretty well, but then no one is going to give you high marks for being good hearted. Maybe you do work hard at appearing to be good and right, but, if you are honest with yourself, you do such things more to make yourself look good than from what really comes from the heart.

One way to do the battery tests is to pay attention to what the outside world thinks of us. How can unbelievers have an accurate take on believers? Maybe they can’t, but even their missing the mark tells us something. Ask your neighbor what he thinks a Christian is. If he answers in terms of what Christians are against, that tells you something. It is true that there are things that we are against which the world thinks is good, especially in the area of sexual practice. And our being against those things will incur resentment.

But I think Jesus’ Sermon on the Mount gives us what is needed to be the kind of lights that will really make a difference in the world and for the world. He tells us that we are the light of the world and that we need to let our light shine. He then teaches the truth of what pleases God, what is a good and righteous life. It includes reconciling with those whom we have offended. It includes treating a woman with respect and not as a sex object. It includes husbands and wives staying together. It includes being true to our word. It includes turning the other cheek and walking the extra mile, giving to those who cannot repay. It includes loving those who treat us as enemies. Being lights mean that we will not show off how religious we are. It rejects greed and calmly trusts the Lord to provide. It replaces anxiety with peaceful hearts. Being lights means that we are more concerned with the logs in our own eyes than we are with the specks in our neighbors eyes. Being lights means that we will do for others what we wish they would do for us.

Now tell me, if we were such lights, what then would our neighbors be saying? If such light was emanating from us, how much penetration do you think it would make in this dark world? It was  through ballot boxes, arguing cases in courts, passing bills, and holding rallies. It is the light of doing good, showing everyone fair play, and acting from sincere love for truth that will make any real difference in the darkness. It is the light that shows the light of Jesus Christ that will change other lives.

It happened to us. Most of us can look to someone who served as a light to us. Someone who loved us, who was a true friend; someone willing to stand up for what is right. Someone willing to share the truth with us. If we grew up in church, even then, it is because we saw the light in those who taught us and lived out their faith before us, that led us to believe. No one is argued into the kingdom of God. We came to believe because we saw action matching the words spoken.

But always remember, that our lights and the lights of everyone else serve but to turn us to the Light that came into this dark world. Jesus calls out, “I am the light of the world. Whoever follows me will not walk in darkness, but will have the light of life.”

Do you want to see? Do you want to see light, see goodness, see righteousness, see truth? Do you want to be light, be good and right and true? Then look to Jesus Christ, the Word who became flesh and dwelt among us. Look to Jesus, who took his light to the top of a cross so that he could draw all people to himself. Look to that light and you will find even yourself becoming light.

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