Ephesians 5:7-8

 

 

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Ephesians 5:7 Therefore do not be partakers with them; (NASB: Lockman)

Greek: me oun ginesthe (2PPMM) summetochoi auton;
Amplified:  So do not associate or be sharers with them. (Amplified Bible - Lockman)
NLT: Don't participate in the things these people do. (NLT - Tyndale House)
Phillips:  Have nothing to do with men like that  (
Phillips: Touchstone)
Wuest:  Stop therefore becoming joint-participants with them (
Erdmans
Young's Literal: become not, then, partakers with them,

REFERENCES

Paul Apple
Albert Barnes
Wayne Barber
Wayne Barber
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J M Boice
John Calvin
Alan Carr
Rich Cathers
Steven Cole
Thomas Constable
Bob Deffinbaugh
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Oliver Greene
David Guzik
Charles Hodge
S Lewis Johnson
John MacArthur
John MacArthur
John MacArthur
J Vernon McGee
F B Meyer
A T Robertson
Ray Stedman
Marvin Vincent
Precept Ministries

Ephesians Outline/Commentary - 135 page Pdf
Ephesians 5
Ephesians 5:6-7: Don't Be Deceived
Ephesians 5:7-10: Walk As Children of Light

Ephesians:5:1-21
Ephesians 5 Body Life (Audio)

Ephesians 5
Ephesians 5:1-10 Walk Like An Ephesian
Ephesians 5:1-7; 8-14; 15-18; 18-20; 21-24; 25-27; 28-33
Ephesians 5:7-14 Children of Light in a Dark World
Ephesians Expository Notes

Ephesians 5:7-14 Living As Lights

Ephesians 5:1-21: Imitate God
Ephesians 5:1-7 As God's Child We Should Follow God
Ephesians 5:8-17  We Are the Children of Light
Ephesians 5
Ephesians 5:3-20 - Commentary
Ephesians 5:3-21 Purity in the Christian Life -Audio or Pdf
Ephesians 5:2-7: Walking in Love - 2
Ephesians 5:8-14: Living in the Light
Ephesians 5:8-14: Living in the Light - Study Guide

Ephesians - Thru the Bible Mp3 Audios
Ephesians 5:8: Walking in the Light
; Chapter 14 - Our Walk
Ephesians 5
Ephesians 5:5-14: New Morality/Ancient Foolishness? 2

Ephesians 5
Ephesians Lesson 1 - 37 pages PDF

THEREFORE DO NOT BE PARTAKERS WITH THEM: me oun ginesthe (2PPMM) summetochoi auton: (Eph 5:11; Numbers 16:26; Psalms 50:18; Proverbs 1:10, 11, 12, 13, 14, 15, 16, 17; 9:6; 13:20; 1Timothy 5:22; Revelation 18:4)

Note: All verbs in bold red indicate commands, not suggestions! Also hold mouse pointer over underlined links for pop up of Scripture which stays open and can be copied.

Therefore (3767) (oun) in light of the truth that those who practice this type of lifestyle (immorality, etc) will not enter heaven. Don't let anyone deceive you for this is a solemn warning. Now he goes on to command his readers to stop participating with them. It doesn't mean we are no longer to be in the world but there is a fine line he draws. And so we are not to date them, marry them, etc, because the danger is that bad company corrupts good morals. Remember that we cannot carry out these commands in your own strength but we all need to be strengthened with power in the inner man by the Spirit of God. Paul is giving a warning to the Gentile saints not to lapse into old vices.

Eadie comments that the conjunction therefore...

is collective: because they are addicted to those sins on which Divine judgment now falls, and continued indulgence in which bars a man out of heaven—become not ye their associates. (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

Wuest paraphrase conveys the sense of Paul's command...

Stop (implying that it was already taking place) therefore becoming joint-participants with them

Be (1096) (ginomai) means to become. The present imperative with a negative commands them to stop an action already in progress or forbidding it from continuing. Paul is warning them against lapsing into their old vices, falling back into the old ruts in the road they once traveled. This is an important command for all of us, for if any man thinks he stands, he better take heed, lest he falls!

Partakers with (4830) (summetochos from sún = with, together, implying a closer relationship, intimacy or union + metochos = a partaker or sharer as one who participates with and shares common blessings with another) means to share in the possession of something, in this case disobedience.

Summetochos was used in the papyri of those who were joint possessors of a house.

What a difference context makes in the meaning of a word, for summetochos was used only one other time in Scripture and that was in chapter 3 where we read...

to be specific, that the Gentiles are fellow heirs and fellow members of the body, and fellow partakers of the promise in Christ Jesus through the gospel (See note Ephesians 3:6)

Jon Courson writes that...

if I sit in the theater and watch people indulging their fleshly lusts on the screen, I am a partaker of their activity. I support it financially when I buy the ticket. And I vote for our culture to keep making this kind of movie whenever I fill a seat to watch it. There’s a better way. We can pray, “You know I struggle with my flesh, Lord. You know I’m tempted by it. But, Lord, I want nothing to do with it. I’ve learned through Your Word and by experience that sin stinks. I’m not going to justify it any longer. I’m not going to excuse it anymore. Instead, I choose to walk in the light.” (Courson, J. Jon Courson's Application Commentary. Nashville, TN: Thomas Nelson )

Charles Hodge writes that...

God is determined to punish the impure and the greedy; so the apostle says, Therefore do not be partners with them. That is, do not be their partners in these sins, which would necessarily expose you to the penalty threatened against them. (See the parallel thought is Psalm 1:1 where the blessed are those who do not associate with the ungodly [see Notes on Psalm 1:1] but associate with the Word of God and the God of the Word - Psalm 1:2,3 - see notes Ps 1:2; 1:3)

 

Ephesians 5:8 for you were formerly darkness, but now you are Light in the Lord; walk as children of Light (NASB: Lockman)

Greek: ete (2PIAI) gar pote skotos, nun de phos en kurio; os tekna photos peripateite (2PPAM)
Amplified: For once you were darkness, but now you are light in the Lord; walk as children of Light [lead the lives of those native-born to the Light].  (Amplified Bible - Lockman)
NLT: For though your hearts were once full of darkness, now you are full of light from the Lord, and your behavior should show it!  (NLT - Tyndale House)
Phillips:  once you were "darkness" but now you are "light". Live then as children of the light. (
Phillips: Touchstone)
Wuest:  for you were at one time darkness, but now you are light in the Lord. As children of light be habitually conducting yourselves (
Erdmans
Young's Literal: for ye were once darkness, and now light in the Lord; as children of light walk ye,

FOR YOU WERE FORMERLY DARKNESS: ete (2PIAI) gar pote skotos: (Eph 2:11,12; 4:18; 6:12; Psalms 74:20; Isaiah 9:2; 42:16; 60:2; Jeremiah 13:16; Matthew 4:16; Luke 1:79; Acts 17:30; 26:18; Romans 1:21; 2:19; 2Corinthians 6:14; Colossians 1:13; Titus 3:3; 1Peter 2:9; 1John 2:8) 

For (gar) introduces an explanation (Always stop and ask "What the for there for?") and in this case Paul gives a special reason for them to remain entirely separate from the sons of disobedience. His point here is that as believers now, their past state (darkness) and their present state (light) are in striking contrast.

As John Eadie explains Paul's word for darkness here...

is the abstract—darkness itself—employed to intensify the idea expressed. Darkness is the emblem and region of ignorance and depravity, and in such a miserable condition they were “once.” But that state was over—“the dayspring from on high” (Lk 1:78, 79) had visited them. (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

You were - is emphatic (placed first in the Greek sentence for emphasis) to throw stress on the fact that all the horrible behaviors he had just described were now behind them. In darkness we chased sin, but beloved, be sober minded, because now sin chases us! It tries to draw us back into the darkness. The idea is that  "You Gentiles who are now believers were. So do not again become darkness!". We need to be constantly mindful from whence we came, that the glorious contrast of truth of where we are seated (in the heavenlies in Christ) and the power we possess (every spiritual blessing in the heavenly places in Christ Jesus) does not become a fading, dim memory. Remembering keeps us humble and thankful and re-kindles in our hearts an appropriately high view of our "so great a salvation".

Formerly (4218) (pote) is a generalization concerning time and means at some time and when referring to past time as in this verse means once or at one time in the past. Paul does not want them to dwell on their past, but he does want them to remember what the darkness was like and how great has been the deliverance from darkness to His marvelous light. Meditate on this truth beloved, the next time you are being tempted to drift back into the darkness to become partakers with those whose only world is darkness. And then make the choice to not put on those filthy, rotten garments you once wore when you were darkness in the old man in Adam. Now, you can say no to the flesh and the siren seductions of darkness because you are light in the Lord! Hallelujah! Walk out now in the light of the victory and surpassing power which Christ Jesus the Lord secured for you at Calvary, the victory over the darkness of the world, the flesh and the devil, the prince of darkness.

Darkness (4655) (skotos from skia = shadow  thrown by an object. Skia it can assume the meaning of skotos and indicate the sphere of darkness) is literally that sphere in which light is absent. It  not the related word skotia which refers more to the consequences of darkness but refers literally to physical darkness, the essence of darkness.

In this passage Paul uses skotos figuratively to describe the abysmal spiritual darkness of every unregenerate person. Note Paul does not say that we were in the darkness but that we were the very essence of darkness!

Since unbelievers are in the darkness of their spiritual blindness, the Bible often uses light to picture salvation (Acts 26:18, 26:23; 13:47; Mt 4:16; Jn 1:4,5,7,8,9; 3:19, 20, 21; 8:12; 9:5; 12:36; 2Co 4:4; 6:14; Ep 5:8, 14; Col 1:12, 13; 1Th 5:5; 1Pe 2:9; 1Jn 1:7; 2:8, 9, 10, cp Is 35:5; 42:6; 61:1).

NIDNTT explains that

In classic Gk. darkness applies primarily to the state characterized by the absence of light (phos) without any special metaphysical overtones. The thought is chiefly of the effect of darkness upon man. In the dark man gropes around uncertainly (Plato, Phaedo, 99b), since his ability to see is severely limited. Thus the man who can see may become blind in the darkness, and no longer know which way to turn. Hence darkness appears as the “sphere of objective peril and of subjective anxiety” (H. Conzelmann, TDNT VII 424). Since all anxiety ultimately derives from the fear of death, the ominous character of darkness culminates in the darkness of death which no man can escape (cf. Homer, Il., 4, 461). Darkness is therefore Hades, the world of the dead, which already reaches out into our world in the mythical figures of the Eumenides, the children of Skotos and Gaia (Soph., Oedipus Coloneus, 40).

Freed from their proper, temporal sense, the words of this group can be used in a metaphorical sense to describe human ways of life and behaviour. Thus they can describe a man’s seclusion or obscurity. They can also indicate the secrecy, furtiveness or deceitfulness of his activity, the abstruseness of his speech, lack of enlightenment, insight and knowledge. “The word does not attain to high conceptual rank in philosophy. Mention of darkness serves to set off light; it has no philosophical content of its own” (TDNT VII 425 f.). (Brown, Colin, Editor. New International Dictionary of NT Theology. 1986. Zondervan)

Skotos can refer to literal darkness as occurred on the day of Jesus' crucifixion (Mt 27:45) or darkness as opposed to light in the creation (2Cor 4:6). Skotos is used as another name for the place of punishment, eternal misery and eternal separation from God.

Skotos figuratively can refer to spiritual or moral darkness (including a lack of understanding) as in the following examples

"(Jesus declared) And this is the judgment, that the light is come into the world, and men loved the darkness rather than the light; for their deeds were evil. (John 3:19)

"(the gospel would) to open their eyes so that they may turn from darkness to light and from the dominion of Satan to God, in order that they may receive forgiveness of sins and an inheritance among those who have been sanctified by faith in Me.' (Acts 26:18)

If we say that we have fellowship with Him and yet walk in the darkness, we lie and do not practice the truth (truth is not only something we should believe and teach but also something we should practice, otherwise our life is a "lie") (1John 1:6)

For He delivered us from the domain of darkness, and transferred us to the kingdom of His beloved Son, (note Colossians 1:13)

The night is almost gone, and the day is at hand. Let us therefore lay aside the deeds of darkness and put on the armor of light. (see note Romans 13:12)

Absence of light leaves room for evil and sin. In this sense darkness may be described as evil.

In his first epistle Peter used skotos figuratively explaining to the believers that...

you are A CHOSEN RACE, A royal PRIESTHOOD, A HOLY NATION, A PEOPLE FOR God's OWN POSSESSION, that you may proclaim the excellencies of Him who has called you out of darkness (the moral and spiritual condition that enshrouds this present world and all those who do not know Christ) into His marvelous light (note 1 Peter 2:9)

Darkness is used to describe the spiritual powers of Satan and his evil empire...

"While I was with you daily in the temple, you did not lay hands on Me; but this hour and the power of darkness are yours." (Luke 22:53)

For our struggle is not against flesh and blood, but against the rulers, against the powers, against the world forces of this darkness, against the spiritual forces of wickedness in the heavenly places. (Ephesians 6:12 note)

In Acts 13:11 skotos is used to refer to physical blindness or inability to see (literally)

Note that skotos is the essence of darkness, darkness itself and as applied to sin is the essence of sin. On the other hand the closely related word skotia speaks more of the consequence of darkness, and so the consequences of sin is the darkness that man has to live in, that darkness entering into Adam in the Garden of Eden.

Ponder what Peter is saying in view of John's declaration...

And this is the message we have heard from Him and announce to you, that God is light, and in Him there is no darkness at all. (1John 1:5)

The opposite of light is absolute darkness. Where God is there can be no darkness. Conversely where the darkness is indicates separation from God. God’s children have been "qualified... to share in the inheritance of the saints in light... delivered... from the domain of darkness and transferred... to the kingdom of His beloved Son" (note Col 1:12-13). The children of the devil, especially his servants who masquerade as ambassadors of light, walk around in spiritual darkness (and separation from God) today, but their darkness is but a foretaste of the utter "black darkness" that awaits them when they die.  Not only is their eternal destiny of purposeless existence horrible but Peter graphically describes their present life as utter emptiness and purposelessness. All life lived without the spiritual goals of glorifying God and worshiping Him is an empty and purposeless existence.

Jesus described the ultimate destiny of the lost declaring...

but the sons of the kingdom (speaking of the Jews who had the special privilege as the chosen nation) shall be cast out into the outer darkness (the final hell); in that place there shall be weeping and gnashing of teeth." (Mt 8:12)

 

"Then the king said to the servants, 'Bind him hand and foot, and cast him into the outer darkness; in that place there shall be weeping and gnashing of teeth (describes the extreme torment that sadly will be true in hell).' (Mt 22:13)

 

"And cast out the worthless slave into the outer darkness; in that place there shall be weeping and gnashing of teeth. (Mt 25:30

Steven Cole commenting on this section of Ephesians writes that...

Darkness symbolizes Satan’s evil domain (Is 49:24,25, Lk 11:21, 22, Col 1:13, 2Ti 2:26, Heb 2:14,15, 1Jn 3:8, 5:19, 1Pe 2:9 Rev 20:2,3),  and the sinful deeds of those who do not obey God. It also represents the spiritual ignorance of those whose sin has blinded their eyes from the light of God’s truth (Eph 4:18; 2Cor. 4:4,). Light pictures the knowledge of the truth that comes when God shines into our lives. As Paul wrote (2Cor. 4:6), “For God, who said, ‘Light shall shine out of darkness,’ is the One who has shone in our hearts to give the Light of the knowledge of the glory of God in the face of Christ.” Light also pictures the holiness of God (1Jn 1:5), who dwells in unapproachable light (1Ti 6:16, Ps 104:2, Hab 3:4, Mt 17:2, Re 21:23, 22:5). So as believers, we are called to walk in the light, just as He Himself is in the light (1Jn 1:7), living with every area of our lives exposed to God (Heb 4:13, Pr 15:3). (Ref)

As Expositor's says...

They were darkness itself, persons...so utterly sunk in ignorance of Divine things, so wholly lost in the evils accompanying such ignorance. (Nicoll, W Robertson, Editor: Expositors Greek Testament: 5 Volumes. Out of print. Search Google)

Darkness describes the character of the life of the unconverted as void of truth and virtue in intellectual and moral matters. It's all the things Paul has already described about the Gentiles in their unconverted state. It's all the things he has described which characterized the old self or old man. Formerly all of those things was the only life they knew.

For example, John writes...

And this is the message we have heard from Him and announce to you, that God is light (He is not like light but He is the Light, the very eternal essence), and in Him there is no darkness (skotia) at all. 6 If we say that we have fellowship (something in common with God -- Who is light) with Him and yet walk (present tense - continually, habitually, as our lifestyle living) in (in the sphere of) the darkness (skotos), we lie and do not practice the truth; 7 but (note the definite contrast) if we walk in the light as He Himself is in the light, we have fellowship with one another, and the blood of Jesus His Son cleanses us from all sin. (1Jn 1:5-7).

Comment: Although you will read a few evangelical commentaries (eg, Constable's Expository Notes) that say that the one habitually walking in darkness is a believer who is simply out of fellowship with God, such an interpretation does not do justice to the general context or the specific verse. If a person is habitually conducting their life in the sphere of darkness, then they are not born again. God is light and in Him there is absolutely no darkness. Therefore, what possible fellowship could light have with darkness (2Co 6:14)?

Steven Cole explains that...

To understand this paragraph, we must see that John is writing against the false claims of the false teachers. Their claims are introduced by the phrase, “if we say" (1Jn 1:6, 8, 10). John here shifts the we from the apostles to a hypothetical group that may include anyone, but especially targets the false teachers. Their first claim was, “We have fellowship with God” (1Jn 1:6), but John says that their lives did not back up their claim. They walked in darkness, they lied, and they did not practice the truth.

Similarly John MacArthur writes that...

In spite of their claims to enlightenment and although the false teachers may have claimed fellowship with Christ, their walking in darkness refuted such claims, and consequently, demonstrated their lack of genuine salvation. The reference to “lie” in 1Jn 1:6b refers to the claim of fellowship in v. 6a. do not practice. This points to their habitual failure regarding the practice of the truth. (MacArthur, J.: The MacArthur Study Bible Nashville: Word or Logos)

 KJV Bible Commentary agrees commenting on 1John 1:6 that...

It is obvious that if there are false teachers or any others who claim to have fellowship (Greek koinonia) with God (having something in common with God), and at the same time (both verbs are in the progressive present in Greek) continue to live according to the standards of darkness only, there is no way around the conclusion that they are lying! (Dobson, E G, Charles Feinberg, E Hindson, Woodrow Kroll, H L. Wilmington: KJV Bible Commentary: Nelson or Logos)

The realm of darkness is presided over by the power of darkness

"While I was with you daily in the temple, you did not lay hands on Me; but this hour and the power of darkness are yours." (Lu 22:53, Col 1:13-note)

Comment: Power is exousia, the right and the might that God allowed Satan to have for that time. Darkness is the domain of Satan.

Satan rules those headed for eternal darkness

but the sons of the kingdom shall be cast out into the outer darkness; in that place there shall be weeping and gnashing of teeth. (Mt 8:12).

These are springs without water, and mists driven by a storm, for whom the black darkness has been reserved. (see note 2 Peter 2:17)

Unregenerate mankind loves spiritual darkness John explaining that...

And this is the judgment, that the light is come into the world, and men loved the darkness rather than the light; for their deeds were evil. For everyone who does evil hates the light, and does not come to the light, lest his deeds should be exposed. But he who practices the truth comes to the light, that his deeds may be manifested as having been wrought in God." (John 3:19-21). (Comment: Quite clearly John explains that people don’t want the light because they like the deeds of the darkness and they do not want to be exposed.)

In Romans 1 explains how men suppressed the truth about God's natural revelation and the subsequent spiritually downward decline...

For even though they knew God, they did not honor Him as God, or give thanks; but they became futile in their speculations, and their foolish heart was darkened. (See notes Romans 1:21)

Isaiah prophesied of the deliverance of the Gentiles from darkness writing...

But there will be no more gloom for her who was in anguish; in earlier times He treated the land of Zebulun and the land of Naphtali with contempt, but later on He shall make it glorious, by the way of the sea, on the other side of Jordan, Galilee of the Gentiles. 2 The people who walk in darkness Will see a great light (Messiah, the Light of the world); Those who live in a dark land, The light will shine on them. (Isaiah 9:1-2 quoted in Mt 4:16)

Luke wrote of the coming of Messiah, the Light of the world...

Because of the tender mercy (strongest word in Gk for feeling of compassion) of our God, With which the Sunrise (Messiah's coming would be like the coming of dawn, light driving away darkness) from on high shall visit us, 79 TO SHINE UPON THOSE WHO SIT IN DARKNESS AND THE SHADOW OF DEATH, to guide (the pix of opening up the way by the removal of obstacles so that the desired goal may be reached) our feet into the way of peace." (Luke 1:78-79)

It is that very darkness from which salvation in Christ delivers sinners.

Again therefore Jesus spoke to them, saying, "I am the light of the world; he who follows Me shall not walk in the darkness, but shall have the light of life. (John 8:12)

(Jesus again said) "I have come as light into the world, that everyone who believes in Me may not remain in darkness. (John 12:46)

For He delivered us from the domain of darkness, and transferred us to the kingdom of His beloved Son, (See note Colossians 1:13)

But you are A CHOSEN RACE, A royal PRIESTHOOD, A HOLY NATION, A PEOPLE FOR God's OWN POSSESSION, that you may proclaim the excellencies of Him who has called you out of darkness into His marvelous light; (see note 1 Peter 2:9)

(Luke records Jesus' charge to Paul as he sent him to the Gentiles to...) Open their eyes so that they may turn from darkness to light and from the dominion (exousia) of Satan to God, in order that (purpose clause) they may receive forgiveness (aphesis - means sending away) of sins and an inheritance (contrast with Ephesians 5:5 - notes) among those who have been sanctified by faith in Me." (Acts 26:18)

So how are believers to respond? What is true about us now in regard to the darkness? Paul summarizes how we should relate to the darkness writing...

The night is almost gone, and the day (of our Lord's return) is at hand. Let us therefore lay aside the deeds of darkness and put on the armor of light. 13 Let us behave properly as in the day, not in carousing and drunkenness, not in sexual promiscuity and sensuality, not in strife and jealousy. 14 But put on (like a new garment) (aorist imperative) the Lord Jesus Christ, and make no provision (present imperative = with negative means stop making provision) for the flesh in regard to its lusts. (See notes Romans 13:12;  13:13; 13:14 )

BUT NOW YOU ARE LIGHT IN THE LORD: nun de phos en kurio:  (Isaiah 42:6,7; 49:6,9; 60:1,3,19,20; John 1:4,5,9; 8:12; 12:46; 1 Corinthians 1:30; 2 Corinthians 3:18; 4:6; 1 Thessalonians 5:4-8; 1 John 2:9-11)

But now - who "you were" showing a dramatic contrast with who "you are".

Light (5457) (phos) can refer to literal light but here is used figuratively as those  enlightened with the truth. Don't miss it - Paul says these Gentile believers are light itself, not a lamp!

Cole writes that...

Paul does not say that we used to be in the darkness, whereas now we are in the light, although this is true (Col. 1:13; John 8:12; 1Pet. 2:9; 1 John 1:5, 6, 7; 2:9). Rather, he says that we used to be darkness, but now we are light in the Lord. Being children of light implies that this profound change comes from God’s power in the new birth. It is an act of His creative power. Just as He at the first created light out of the darkness, so now He has changed us from being darkness itself into being light in the Lord. Most of us have had the experience of visiting a cave where the guide turned off all of the lights for a few seconds (which always seem like minutes!). You can’t even see your hand in front of your face. For a few awful seconds, you realize what it would be like to be totally blind.

Paul says that we formerly were darkness. We were spiritually blind. We not only didn’t see God’s glory and truth, we didn’t have the ability or desire to see such things. We didn’t sense our need for the Savior, because we thought we were good enough to go to heaven and we didn’t understand the absolute holiness and justice of God. So we lived entirely for ourselves and our own pleasure, avoiding the thought of death and eternity. But, when God saved us (Titus 3:5, cp Gal 2:16, 17, 18, 19, 20 21), He opened the eyes of our understanding so that we saw “the Light of the knowledge of the glory of God in the face of Christ” (2Cor. 4:6). We saw our true condition as guilty sinners, but we also saw the all sufficiency of Jesus and His death on the cross to cover all our sins. We had a new understanding of God’s Word and a new desire to know God and His truth more and more. We now hate the sin that we formerly lived in and we long to be like our Savior, holy in all our ways. We now walk in the light, rather than in darkness, because God has made us light in the Lord. While some of us (and I am one) can’t say exactly when this change took place, you know that it took place, because you know that God changed your heart. “You were formerly darkness, but now you are Light in the Lord” (Ep 5:8). To walk as children of light, you must be a child of light by God’s saving power. (Ref)

In his book Illustrations of Bible Truth, H. A. Ironside included the story of a new convert who gave his testimony during a church service. With a smile on his face and joy in his heart, the man related how he had been delivered from a life of sin. He gave the Lord all the glory, saying nothing about any of his own merits or what he had done to deserve the blessings of redemption. The person in charge, who was very legalistic, didn’t fully appreciate the reality of salvation by grace through faith alone, apart from human works (Eph 2:8,9). So he responded to the young man’s comments by saying,

“you seem to indicate that God did everything when He saved you. Didn’t you do your part before God did His?”

The new Christian jumped to his feet and said,

“Oh yes, I did. For more than 30 years I ran away from God as fast as my sins could carry me. That was my part. But God took out after me and ran me down. That was His part.”

Expositors Greek Testament comments that...

The completeness of the change is indicated again by the use of the abstract term—so possessed and penetrated were they by that truth that they could be described not simply as enlightened but as themselves now light. And this ‘in the Lord,’ for it was in virtue of their fellowship with Christ that this new apprehension of things came to them, transforming their lives. (Nicoll, W Robertson, Editor: Expositors Greek Testament: 5 Volumes. Out of print. Search Google)

Lord (2962) (kurios) means lord, master, owner or the one who has absolute ownership  power. Jesus is referred to some ten times as Savior and some seven hundred times as Lord. Kurios translates Jehovah (LORD in OT) in Septuagint (LXX) 7000 times. Kurios signifies sovereign power and absolute, supreme authority. It is the one who has absolute ownership and uncontested power.

Barber explains now you are light in the Lord this way...

It is all because of Him. Outside of Him there is no light. In Him is where the light is. Remember, I am not the light. He is the light. I am light because the Light is within me. He has come in and turned it on, and now I can understand and comprehend. I can walk the way He wants me to walk. His Spirit can teach me the things I need to know, and I can live a life that reflects the essence of light. We were once darkness. Now we have been made light. Not just put in the light, we are now made light because He is in us. The Light is in us (Jn 8:12, 1Jn 2:9, 10, cp Jn 3:20, 21, 11:10, 12:36)...We are accountable for sin now...Now that you are in Christ, you are responsible to call them by name because you have light within you and you know what you are doing is by your own choice. You choose not to put that garment on (the garment of the "Old Man"). You have light in you. That is why confession of sin is such an important word in the vocabulary of the believer. (Reference)

 WALK AS CHILDREN OF LIGHT: os tekna photos peripateite (2PPAM): (Eph 5:2; Isaiah 2:5; Luke 16:8; John 12:36; Galatians 5:25; 1Pe 2:9, 10, 11; 1John 1:7)

Paul had just reminded them of their new position in Christ (children of light), but position is not a guarantee that we will live that way consistently. And so in this verse Paul gives a command saying in essence "Make it your habit to live what you are and Whose you are!", in other words,  in a way consistent with your character as redeemed men and women illuminated and sanctified by virtue of your union with the Lord Jesus Christ (See discussion of in Christ and in Christ Jesus ).

Walk (4043) (peripateo from peri = about, around + pateo = walk, tread) (Click word study on peripateo) means literally to walk about here and there or to tread all around. Peripateo then came to mean, to make one’s way, to make progress, to make due use of one’s opportunities and finally (as used by Paul in Ephesians), to live, to regulate one’s life, to conduct one’s self. Most of the NT uses refer to the daily conduct of one's life or how one orders their behavior or passes their life.

In contrast to those who walk in spiritual darkness, Paul uses the present imperative to command believers to continually walk in the light into which they have been transferred. Keep walking in the light, step by step, ever making progress.

Walk as children of light for as Paul says

"what fellowship has light with darkness?" (2Cor 6:14)

The point is that there is none. Thus it makes "good sense" that those who walk in the darkness (as manifest by their deeds just described) would not enjoy fellowship in the Kingdom of Light in the presence of the One Who Alone is the Light of the World and in Whom there is no darkness at all.

John Eadie explains that...

Negatively they were not to be partakers; but neutrality is not sufficient—positively they were to walk as children of the light. “As children of light,” they were to show by their conduct that they loved it, enjoyed it, and reflected its lustre. Their course of conduct ought to prove that they hated the previous darkness, that they were content with no ambiguous twilight, but lived and acted in the full splendour of the Sun of Righteousness, hating the secret and unfruitful deeds of darkness referred to in the following context. First, the apostle has referred to love as an element of Christian walk, Eph 5:1,2 (note); and now he refers to light as an element of the same walk; different aspects of the same spiritual purity; love, and not angry and vengeful passions; light, and not dark and unnameable deeds. (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

Children (5043) (teknon from tikto = bring forth, bear children, be born) means literally "a born one" and refers to a child as viewed in relation to the one who bore him (in this case of course the Spirit of the Living God). It follows that teknon takes on special theological significance when the Bible calls believers the children of God.  God's spiritual children possess His divine nature (not little gods), the nature of light. In Ephesians 5:1, Paul used teknon in his reference to the Gentile saints as beloved children (teknon).

Children of light - Describes the nature of the Father (1Jn 1:5) that is in us now which equates with His light that is within us (Jn 8:12, 12:36, Jn 3:20, 21, 11:10).. We are born of Him Who is light and we are the children of light. It was because of His light that we saw our sinfulness and became His children.

Light (5457) (phos) is used figuratively of believers who shine forth Christ in them the hope (absolute certainty of future good) of glory. Paul is giving his warning to those who are children of God, thus light in the Lord, thus, children of light (cp 1Th 5:4, 5, 6-note)

Expositors adds that...

If these Ephesians were now ‘light in the Lord,’ it was not for themselves only but for others. They were called to live a life beseeming those to whom Christian enlightenment and purity had become their proper nature.” (Ibid)

Jesus calls for all of His disciples to be lights declaring...

You are the light of the world. A city set on a hill cannot be hidden. Nor do men light a lamp, and put it under the peck-measure, but on the lampstand; and it gives light to all who are in the house. Let your light shine before men in such a way that they may see your good works, and glorify your Father who is in heaven. (see notes Matthew 5:14; 15; 16)

Charles Hodge writes that...

As light stands for knowledge, and as knowledge, in the scriptural sense of the word, produces holiness, and holiness happiness, so darkness stands for ignorance, and such ignorance inevitably produces sin, and sin misery. Therefore, the expression you were once darkness means, “you were ignorant, polluted, and wretched.” But now you are light in the Lord—i.e., in virtue of union with the Lord, you are enlightened, sanctified, and blessed. Live as children of light—i.e., as the children of holiness and truth. Children of light means “enlightened,” and “children of famine” means the famished: see Ephesians 2:2. The exhortation is that they should walk in a way consistent with their character, as people illuminated and sanctified by their union with the Lord Jesus. (Ephesians 5:3-20)