Ephesians 5:15-16

 

 

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Ephesians 5:15 Therefore be careful * how you walk, not as unwise men but as wise, (NASB: Lockman)

Greek: Blepete (2PPAM) oun akribos pos peripateite, (2PPAI) me os asophoi all' os sophoi,
Amplified: Look carefully then how you walk! Live purposefully and worthily and accurately, not as the unwise and witless, but as wise (sensible, intelligent people) (Amplified Bible - Lockman)
KJV: See then that ye walk circumspectly, not as fools, but as wise,
NLT
:  So be careful how you live, not as fools but as those who are wise. (
NLT - Tyndale House)
Phillips: Live life, then, with a due sense of responsibility, not as men who do not know the meaning and purpose of life but as those who do. (
Phillips: Touchstone)
Wuest:  Be constantly taking heed therefore how accurately you are conducting yourselves, not as unwise ones but as wise ones  (
Erdmans
Young's Literal: See, then, how exactly ye walk, not as unwise, but as wise

REFERENCES

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

Ephesians Outline/Commentary - 135 page Pdf
Ephesians 5
Ephesians 5:15-17 Walking as Light in a World of Darkness
Ephesians:5:1-21
Ephesians 5 Body Life (Audio)

Ephesians 5
Ephesians 5:1-7; 8-14; 15-18; 18-20; 21-24; 25-27; 28-33
Ephesians 5:15-21 Walking Carefully in an Evil Day
Ephesians 5:15-17 Walking Wisely; God's Wisdom for Families
Ephesians Expository Notes

Ephesians 5:15-21 Walking Wisely

Ephesians 5:16: Preciousness of Time-Redeeming It
Ephesians 5:16: Preciousness Importance of Time

Ephesians 5:1-21: Imitate 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)
Ephesians 5:15 Walking in Wisdom, Part 1
Ephesians 5:16-17 Walking in Wisdom, Part 2
Ephesians - Thru the Bible Mp3 Audios
Ephesians 5:15-16 The Wise Use of Time
Ephesians 5:15-20 Urgency And Gratitude 

Ephesians 5
Ephesians 5:15-20: Watch How You Walk

Ephesians 5
Ephesians Lesson 1 - 37 pages PDF

THEREFORE BE CAREFUL HOW YOU WALK: blepete (2PPAM) oun akribos pos peripateite, (2PPAI): (Eph 5:33; Mt 8:4; 27:4,24; 1Th 5:15; He 12:25; 1Pe 1:22; Re 19:10) (Ex 23:13; Mt 10:16; 1Co 14:20; Php 1:27; Col 1:9; 4:5)

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.

Be as careful and wise as Jonathan Edwards was when he wrote in his diary at age twenty

Resolved, never to lose one moment of time, but to improve it in the most profitable way I possibly can. (I would add the prayer Ps 90:12)

Moule has some great introductory comments to Ephesians 5:15-21 writing that...

THE Ephesians have learnt much now of the details of the holy life, and the last words which they (and we) have heard about it have pointed the thought full upon an element in it which is vital to its health—holy action, holy service. The believer, "light in the Lord," is to shed the light which he receives. There is to be a warm hearth-fire in his own soul's chamber, and a lamp fed with heaven's own sunshine is to hang from its ceiling. But it is also to be a radiant point in the dark world, finding way for its searching beneficent brightness through the windows of the soul, from the beacon-tower of the life, The range of penetration may be vast, or it may be very small. It may command a great region of the earth, or many regions; it may fill an age of time, it may affect all the ages; such was the range of St Paul's radiation, for example. Or it may light up one small neighbourhood, one poor home, the visitors to one sick-room; it may be limited in time by only a fragment of the disciple's one short life; such was no doubt the range of radiation for many an Asian saint then, as it is for many an English saint now. But the point is that there is intended to be radiation outward where there is light within. The Master's service is to be the dear object of the redeemed life. The sacred light is given indeed for the being's own bliss, rich and large; but it is never given to terminate there. And they best meet the Master's will who most willingly and most continually so keep the windows clear that the light within may radiate around, for conviction, and for gladness, just as freely and as far as may be.

Happy they who, by His grace, so serve Him. Do we not know such lives? They "cannot be hid"—not because they advertise themselves; that is the very last thing they do. But it is unmistakable that they are enjoying a great light within, and it "will out." Such (to keep close to our own time, and to no very extended circle) were William Pennefather, Arthur Blackwood, Frances Havergal. Such was that great light-bearer so recently called from us, D. L. Moody. Such are cherished names still among us, known to thousands who owe them more than they can ever tell, for the light brought by them into the thick darkness of worldliness, sin, doubt, and fear. But there have been, and there are, countless others whom no Christian history will ever name, but who live in transfigured hearts on which they have shone. Their "record is on high."

The Apostle comes now to a few more lines of general caution and precept, before he approaches his final topic, the Christian Home. He has to appeal again for a grave remembrance that the "walk in the light" is no mere promenade, smooth and easy, but a march, resolved and full of purpose, cautious against the enemy, watchful for opportunity for the King, self-controlled in every habit, and possible only (if it is to be a reality) in the power of the eternal Spirit. It is to be a walk, onward and upward, of holy and habitual praise, of fellowship in spiritual help, and of a mutual submission which means forgetfulness of self in the recollection of others, in the Lord. (Rev. Handley C. G. Moule, D.D. Ephesian Studies: Expository Readings on the Epistle of Saint Paul to the Ephesians)

Therefore - This term of conclusion draws us back to the immediate context, in which Paul has just given the command to be continually awake. But it undoubtedly also goes back to the beginning of this practical section where Paul implored his readers to "walk in a manner worthy of the calling with which you have been called." (Eph 4;1-note) adding that they were to "walk no longer just as the Gentiles also walk" (Eph 4:17-note). In chapter 5 Paul continued to emphasize the importance of the believer's walk giving the command to continually "Walk in love" (Eph 5:2-note) like Christ and to continually "Walk as children of Light" since they are now light in the Lord (Eph 5:8-note). And so here in verse 15, Paul picks up the theme of a worthy walk, emphasizing that it is to be a careful walk, a circumspect walk (redeeming time) and a controlled walk (filled with the Spirit).

Be careful how you walk -  carries the idea of looking around carefully so as not to stumble, which Paul explains equates with walking intelligently and not in ignorance.

Bishop J C Ryle alluded to a careful...walk when he said...

We may depend upon it as a certainty that where there is no holy living there is no Holy Ghost.

A W Tozer echoed this same thought when he said...

The filling of the Holy Spirit (see Ep 5:18) brings a sharp separation between the believer and the world.

John Stott introduces this section writing that...

Paul’s next little paragraph is based upon two assumptions, first that Christians are sophoi,—wise people, not fools—and secondly that Christian wisdom is practical wisdom, for it teaches us how to behave. His word for to ‘behave’ throughout the letter has been a Hebrew concept, to ‘walk’. Our Christian walk or behaviour, he has written, must no longer be according to the world, the flesh and the devil (Ep 2:1, 2, 3), or like the pagans (Ep 4:17). Instead, it must be ‘worthy’ of God’s call, ‘in love’, and ‘as children of light’ (Ep 4:1; 5:1; 5:8). Now he adds a more general exhortation to us to behave like the wise people he credits us with being: look carefully how you walk, he writes. Everything worth doing requires care. We all take trouble over the things which seem to us to matter—our job, our education, our home and family, our hobbies, our dress and appearance. So as Christians we must take trouble over our Christian life. We must treat it as the serious thing it is. ‘Be most careful then how you conduct yourselves: like sensible men, not like simpletons’ (neb). (Stott, J. R. W. God's New Society : The Message of Ephesians. Downers Grove, Ill.: InterVarsity Press)

Circumspectly (KJV) (199) (akribos) means characterized by exactness, thoroughness, precision, accuracy in addition to the associated idea of looking, examining, and investigating something with great care and alertness. Akribos pertains to strict conformity to a norm or standard, involving both detail and completeness, with focus on careful attention. In context akribos refers to ethical behavior with a focus on careful attention especially regarding the dangers and deceptions that continually assault us from our mortal enemies, the world, the flesh and the devil.

See to it that you walk circumspectly (akribos - accurately, diligently, carefully). Walk warily, exactly or diligently. Our English word circumspect is from the Latin circum- = around + specere = look and conveys the literal picture of looking around or figuratively being cautious. One who is walking circumspectly is one who is surveying all circumstances and possible consequences before acting or deciding. A great word picture!

The idea of akribos is that our walk is in strict conformity to a standard, and as such calls for carefulness against any departure from what is proper to a believer's walk. How does one accomplish this charge to be careful how we walk? By not walking unwisely, but wisely, as those who are continually redeeming for themselves the precious time God gives,  by understanding His good and acceptable and perfect will and by not being filled with wine but being filled with His Spirit.

Note that the NAS translates the adverb akribos (199) somewhat vaguely. Here are other translations that translate akribos more literally...

Be constantly taking heed therefore how accurately (akribos) you are conducting yourselves... (Wuest)

See, then, how exactly (akribos) ye walk (Young's Literal)

See then that ye walk circumspectly (akribos)... (KJV)

See to it that you walk carefully, with circumspection and not carelessly

There are 5 uses of akribos in the NT...

Matthew 2:8 And he (Herod in seeking to kill the newborn Jesus) sent them (magi) to Bethlehem, and said, "Go and make careful search for the Child; and when you have found Him, report to me, that I too may come and worship Him." (Comment: God warned them in a dream not to return to Herod, Mt 2:12)

Luke 1:3 it seemed fitting for me as well, having investigated everything carefully from the beginning, to write it out for you in consecutive order, most excellent Theophilus;

Acts 18:25 This man had been instructed in the way of the Lord; and being fervent in spirit, he was speaking and teaching accurately the things concerning Jesus, being acquainted only with the baptism of John;

Ephesians 5:15 Therefore be careful (see discussion above) how you walk, not as unwise men, but as wise, (YLT: See, then, how exactly ye walk, not as unwise, but as wise)

1Thessalonians 5:2 (note) For you yourselves know full well that the day of the Lord will come just like a thief in the night.

Therefore (3767) (oun) introduces a logical result or inference from what precedes (so, consequently, thereupon, then)

Be careful (991) (blepo) means to look at, behold, discern mentally, observe,  perceive, consider, contemplate, look to in the sense of taking care, take heed. It means perceive with your eyes. Have your eye on so as to beware of. Blepo generally denotes simply a voluntary observation or taking notice of something or someone.

The present imperative is commands one to continually pay especially close attention to how they walk. “Be constantly taking heed how accurately you are conducting yourselves.” We need to remember that our heart is more deceitful than all else and that the enemy of our soul constantly prowls around and his desire is for our soul.

Jesus used blepo in a similar sense of contemplating in order to beware...

And Jesus answered and said to them, "See to it (blepo = present imperative) that no one misleads you. For many will come in My name, saying, 'I am the Christ,' and will mislead many. (Mt 24:4-5) (Comment: He is speaking of the times especially preceding His return.)

And He was giving orders to them, saying, "Watch out! Beware (blepo = present imperative) of the leaven of the Pharisees and the leaven of Herod." (Mark 8:15)

And in His teaching He was saying: "Beware (blepo = present imperative) of the scribes who like to walk around in long robes, and like respectful greetings in the market places... (Mark 12:38)

Paul used blepo with a similar meaning in Colossians writing...

See to it (blepo = present imperative) that no one takes you captive through philosophy and empty deception, according to the tradition of men, according to the elementary principles of the world, rather than according to Christ. (See note Colossians 2:8)

The apostle John uses blepo to warn the believers to...

Watch (blepo = present imperative) yourselves, that you might not lose what we have accomplished, but that you may receive a full reward. (2John 1:8) (Comment: All believers will receive praise at the judgment or bema seat of Christ according to 1Cor 4:5, but some believers shall suffer loss of their rewards as described in 1Cor 3:11-15)

In Hebrews the writer warns...

Take care (blepo = present imperative), brethren, lest there should be in any one of you an evil, unbelieving heart, in falling away from the living God. (see note Hebrews 3:12)

Wuest adds that you are to...

see to it that your conduct is accurate with respect to the demands of the Word of God. It is like a motorist accurately following on the right side of the center line dividing traffic. (Wuest, K. S. Wuest's Word Studies from the Greek New Testament: Eerdmans)

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.  

To walk circumspectly is to walk in the light of our exalted position and privilege as beloved children of God. To walk in an unwise manner means to descend from the high plane and privilege to the profane practices of the fallen world. To walk wisely is to redeem each day, "buying up" every precious moment God gives.

The Amplified Version conveys the thrust of Paul's command rendering it...

Look carefully then how you walk! Live purposefully and worthily and accurately... (Ed note: Good advice. God's formula for real success!)

Wayne Barber writes that...

Ephesians 5:15 tells us we are to be very careful as we walk. When we put on this new garment and walk out into a world penetrated by darkness, this garment, Christ in us (cp Col 1:27), has the power to first of all refuse the deeds of darkness, secondly reprove the deeds of darkness, and thirdly remove the deeds of darkness. Light puts out darkness. Folks, when you put on the garment, when you are living what you have in Jesus Christ, it is a powerful weapon against the darkness that is residing in this world. (Ephesians 5:15-17 Walking as Light in a World of Darkness)

NOT AS UNWISE MEN BUT AS WISE: me os asophoi all' os sophoi,: (2Samuel 24:10; Job 2:10; Psalms 73:22; Proverbs 14:8; Matthew 25:2; Luke 24:25; Galatians 3:1,3; 1Timothy 6:9; James 3:13)

Now Paul explains what he means by walking carefully...first the negative, then the positive.

(Not) Unwise (781) (asophos from a = without + sophos = wise) (used only in Ep 5:15) means without wisdom and so unwise, silly or foolish. This adjective describes one who lacks the power of proper discernment.

To walk any way except in the path of holiness, the ancient paths, turning neither to the left or the right, is to walk as a fool!

The NKJV has a good rendering...

See then that you walk circumspectly, not as fools but as wise

To walk circumspectly and thus wisely is to live in the light of our position as God’s children. To walk as fools means to descend from this high plane to the conduct of worldly men.

Wise (4680) (sophos) is the practical application of acquired knowledge. It describes the ability to use knowledge for correct behavior (1Co 6:5). Sophos describes understanding that results in wise conduct.

The wise walk of wisdom in context calls for each of us to redeem the time, "buying up" every (spiritual) opportunity presented to us by God (Eph 5:16). Wisdom is revealed in godly living. It calls for us not to be controlled by wine but to be continually controlled by the Holy Spirit (Eph 5:18)

There are 20 uses of sophos in the NT - Mt. 11:25; 23:34; Lk. 10:21; Ro 1:14, 22; 16:19, 27; 1Co 1:19, 20, 25, 26, 27; 3:10, 18, 19, 20; 6:5; Eph. 5:15; James. 3:13

In short we are to be walking as God expects (His will) and enables (by His indwelling Spirit) believers to walk. To walk circumspectly is to live in the light of our position, privilege and power as God’s children. It's to attain to our potential as men and women who are in Christ (see in Christ and in Christ Jesus). To walk as fools means to descend from this high plane to the conduct of worldly men.

John Eadie writes that...

If the Ephesian Christians walked without taking heed to their ways, then they walked as fools do, who stumble and fall or miss the path. Wisdom, not in theory, but in practice—wisdom, and not mere intelligence — was to characterize them; that wisdom which preserves in rectitude, guides amidst temptations, and affords a lesson of consistency to surrounding spectators.

And if there be any allusion to Eph 5:11, then the inferential meaning is—it would be the height of folly to rebuke that sin which the reprover is openly committing; to condemn profane swearing, and barb the reprimand with an oath; or exemplify the vices of wrath and clamor in anathematizing such as may be guilty of them. It is strange infatuation to be obliged, in pointing others to heaven, to point over one's shoulder. And one peculiar proof and specimen of wisdom is now given (in Eph 5:16) (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians).

><> ><> ><>

Check Your Work-I'm getting pretty good at math. That's because every day my son Steve and I have a little math session. He does his 30 junior high math problems, and I help him check them over. Sometimes we even get them all right.

As I go over Steve's math, I notice that he understands how to do his problems. In fact, in some areas he's better at it than I am. But occasionally, despite knowing how to do the problem, he gets the wrong answer. He either gets a little sloppy in using the right formula or he just doesn't check his answers carefully.

Aren't we all a little like that in our Christian life? We know what we should do. We have a good understanding of how to live the Christian life, but we get careless or lazy. We know better, but we fail.

For instance, we know we aren't supposed to gossip. But before we know it, we're roasting a fellow Christian. Or this: We know God wants us to keep our mind and heart pure, but we let down our guard and watch a TV program or movie we know is not edifying.

It's true, isn't it? We all get a little sloppy in how we live for God. Let's be more careful and pay closer attention to our Christian walk (Ephesians 5:15). Let's make sure we're doing quality work for our heavenly Father. —J D Branon (
Our Daily Bread, Copyright RBC Ministries, Grand Rapids, MI. Reprinted by permission. All rights reserved)

Lord, help me to apply Your Word
And move it from my head
To actions that won't shame your Name
But honor You instead. —Sper

Give your all for Jesus,
He gave His all for you.

 

Ephesians 5:16 making the most of your time, because the days are evil. (NASB: Lockman)

Greek: exagorazomenoi (PMPMPN) ton kairon, hoti ai hemerai ponerai eisin. (3PPAI)
Amplified: Making the very most of the time [buying up each opportunity], because the days are evil.  (Amplified Bible - Lockman)
KJV: Redeeming the time, because the days are evil.
NLT
:  Make the most of every opportunity for doing good in these evil days. (
NLT - Tyndale House)
Phillips: Make the best use of your time, despite all the difficulties of these days  (
Phillips: Touchstone)
Wuest:  buying up for yourselves the opportune time, because the days are pernicious. (
Erdmans
Young's Literal: redeeming the time, because the days are evil;

MAKING THE MOST OF YOUR TIME: exagorazomenoi (PMPMPN) ton kairon: (Romans 13:11; Galatians 6:10; Colossians 4:5)

Redeeming the time (KJV)

Solomon gives an excellent parallel thought from the Old Testament...

Whatever your hand finds to do, verily, do it with all your might; for there is no activity or planning or knowledge or wisdom in Sheol where you are going. (Ecclesiastes 9:10)

How does a believer walk wisely and not walk foolishly? Paul says one way is by making the most of your time. In other words the first sign that a person is wise is that he is sensitive to how he uses his time. He makes a disciplined use of his time. (cp Moses' prayer Ps 90:12) We all understand that time is valuable, for even the lost world says "time is money". We all have the same amount of time, but in this context as explained more fully below, Paul is not speaking so much of time in general but of the opportunities that are placed before us. In the next segment Paul explains that wise people discern the will of God (Ep 5:17).

Someone once wrote a wise saying which is so apropos in regard to the opportunities God gives each believer...

Lost, yesterday, somewhere between sunrise and sunset,
two golden hours, each set with sixty diamond minutes.
No reward offered, for they are gone for ever.

Making the most (1805) (exagorazo from ek = out or from -- If something is in something else, then ek describes separating it in respect to place, time, source or origin + agorázo = buy, acquire possessions or services in exchange for money with the result that whatever has been bought is the buyer's by  right of possession <> from agora = market place where things were exposed for sale,  a forum, a place in which the people assemble and where public trials were held) means literally to buy out of (ek = out of) the market place. It means to completely redeem. Click for word study on exagorazo. Believers are to take advantage of every spiritual opportunity  because we know that the night is coming when no one can work. There is an open window in time for the gospel. We must seize the moment!

Eadie writes that...

The “unwise” allow the propitious moment to pass, and it cannot be recalled. They may eulogize it, but they have missed it. The “wise,” on the other hand, who walk correctly, recognize it, appreciate it, take hold of it, make it at whatever sacrifice their own, and thriftily turn it to the best advantage. They redeem it (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

Pastor Ray Pritchard writes that exagorazo...

is a word from the market place. You go down to your supermarket and look for bargains because you know they will not last long; they are passing, changing. Therefore, make the most of them and buy them up. This is exactly the word he employs here. Buy up the opportunities which are created constantly by the evil days. (Ephesians 5:15-20: Watch How You Walk)

Warren Wiersbe laments...

 How foolish to stumble along through life and never seek to know the will of the Lord! Instead of walking “accurately” (which is equivalent to “circumspectly”), they miss the mark, miss the road, and end up suffering on some detour. God wants us to be wise and understand His will for our lives. As we obey His will, we “buy up the opportunities” (redeem the time, v. 16) and do not waste time, energy, money, and talent in that which is apart from His will. Lost opportunities may never be regained; they are gone forever. (Wiersbe, W. W. Wiersbe's Expository Outlines on the New Testament. Wheaton, Ill.: Victor Books)

REDEEM THE TIME
"NOW"

James Montgomery Boice, the great Christian pastor and writer, who redeemed the time well until his untimely death at age 61 (June 15, 2000) wrote that there are...

a number of biblical words for time and contrasted kairos, which deals with the significant moment or opportunity, and chronos, which deals only with time's duration. There is another biblical word which I did not mention then but which I turn to now as an appropriate closing: the word nun. It means "now," and it occurs in verses which show that the kairos in which we live, the pregnant present moment, is eternally significant. "Once you were not a people, but now you are the people of God; once you had not received mercy, but now you have received mercy" (1Pe 2:10-note). "Blessed are you who hunger now, for you will be satisfied. Blessed are you who weep now, for you will laugh" (Lk 6:21). "Now is the time of God's favor, now is the day of salvation" (2Co 6:2).If you and I are going to redeem time, as wise men and women, we had better do it now, because there may be no opportunity tomorrow. If we are to understand the will of God, now is the moment that counts. If we are going to be filled with God's Spirit, now is when we need filling. (Bolding and italics added for emphasis) (Commentary on Ephesians)

In Ephesians 5:15 and the parallel passage in Colossians 4:5 (note) Paul uses the middle voice which conveys a "reflexive" sense to exagorazo - the idea then is of buying up for oneself, of buying up every opportunity (kairos),  turning each opportunity to the best advantage for oneself.

Conduct (present imperative) yourselves with wisdom toward outsiders, making the most (exagorazo = present tense = continually) of the opportunity. (See note Colossians 4:5)

Comment: Wuest translates it  "buying up for yourselves the strategic, opportune time." The idea is to be habitually, continually ''buying up'' all that is anywhere to be bought and not allowing the moment to pass by unheeded or unused but to make it one’s own.

Thayer adds that exagorazo as used in (Eph 5:16) and (Col 4:5) means to

Buy up, buy up or out of for one's self and so to make wise and sacred use of every opportunity for doing good, so that zeal and well doing are as it were the purchase money by which we make the time our own.

The venerable Pastor Harry Ironside wisely reminds us that

Time is given us to use in view of eternity.

MacArthur writes that exagorazo

has the basic meaning of buying, especially of buying back or buying out. It was used of buying a slave in order to set him free; thus the idea of redemption is implied in this verse. We are to redeem, buy up, all the time that we have and devote it to the Lord. The Greek is in the middle voice, indicating that we are to buy the time up for ourselves—for our own use but in the Lord’s service. (MacArthur, J: Ephesians. Chicago: Moody Press)

Hodge adds that Ephesians 5:15 can be translated

availing yourselves of the occasion, i.e. improving every opportunity for good. (Hodge, C. Commentary on Ephesians)

The UBS Handbook Series adds that

The readers are being told to seize and use every opportunity to carry on their Christian witness, because these are evil days, In some languages it is necessary to specify what is involved in every opportunity. Accordingly, it may be necessary to translate make good use of every opportunity you have as “every time you can do something good you should” or “you should use every chance to do good. (Bratcher, R. G., & Nida, E. A. A Handbook on Paul's letter to the Ephesians. UBS handbook series. New York: United Bible Societies)

The idea then is turning each season (kairos) to the best advantage since none can be recalled if missed. 

Every time you can do something good you should.

As someone else has said

Beware of wasting the present. Instead of killing time, redeem your spare moments today. Wasting the gift of time insults the Giver of time.

Redeem the time! God only knows
How soon our little life may close,
With all its pleasures and its woes,
Redeem the time!        
 — Anonymous

The idea is not to make best use of time as such (although that is certainly advisable), which is what we should do in the sense of not wasting it, but of taking advantage of the opportunities that present themselves.

Expositor's Greek Testament sums up the essence of Paul's charge in this section writing that...

"The sense comes to be this -- the character of wisdom by which their walk was to be distinguished was to show itself in the prompt and discerning zeal with which they made every opportunity their own, and suffered no fitting season for the fulfilment of Christian duty to pass unused." (Nicoll, W Robertson, Editor: Expositors Greek Testament: 5 Volumes. Out of print. Search Google)

An ancient Greek statue depicted a man with wings on his feet, a large lock of hair on the front of his head, and no hair at all on the back. Beneath was the inscription:

“Who made thee? Lysippus made me.

What is thy name? My name is Opportunity.

Why hast thou wings on thy feet? That I may fly away swiftly.

Why hast thou a great forelock? That men may seize me when I come.

Why art thou bald in back? That when I am gone by, none can lay hold of me.”

Buying Time -- Consider this: “If we had to buy time, would there be any difference in how we would spend it? Would the days of our lives be used more wisely?” That’s what time management consultant Antonio Herrera asked the participants in a seminar he conducted on the subject. Then Dr. Herrera became more specific. He asked, “What if you had to pay in advance $100 an hour for the time allotted to you? Would you waste it?” The answer should be obvious. Of course, we can’t put a price tag on the minutes and hours we possess. They are given to us freely. But that doesn’t excuse us from using them conscientiously, carefully, and wisely. The giver of time is God Himself, and that places a far greater value upon it than any monetary figure could suggest. We must therefore use our time intelligently, taking advantage of opportunities it provides for us to serve the Lord and to do His will.

TIME: Three most difficult things to do are: keep a secret, forget injury, and make good use of your leisure time (it's really not yours anyway but His...He's just "loaning" it to you.)

God set a goal, yet gave the choice
To mortals how time may be spent,
Admonishing that worth, not length,
Values time's accomplishment.
                            — Mortenson

Solomon wisely exhorted his readers...

Whatever your hand finds to do, verily, do it with all your might; for there is no activity or planning or knowledge or wisdom in Sheol where you are going. (Eccl 9:10)

Shakespeare wrote,

There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune;
Omitted, all the voyage of their life
Is bound in shallows and in miseries.
(Julius Caesar, 4.3.217)

Time (2540) (kairos) (Click word study on kairos) means a point of time or period of time, time, period, frequently with the implication of being especially fit for something and without emphasis on precise chronology. It means a moment or period as especially appropriate the right, proper, favorable time (at the right time). Kairos speaks of a limited period of time, with the added notion of suitableness ("the suitable time", "the right moment", "the convenient time"). Kairos refers to a distinct, fixed time period, rather than occasional moments.

In a sense kairos alludes to the brevity of life, which begs one to pause and ponder his or her life like flowering grass, here today, gone tomorrow and in light of this truth to take a sincere, possibly sobering inventory of our daily activities of thought, word and deed!

Kairos is not so much a succession of minutes (Greek chronos 5550), but a period of opportunity. Chronos refers to chronological time, to clock time or calendar time, to a general space or succession of time. Kairos, on the other hand, refers to a specific and often predetermined period or moment of time and so views time in terms of events, eras, or seasons. In other words, kairos defines the best time to do something, the moment when circumstances are most suitable, the psychologically "ripe" moment.

In rhetoric kairos is "a passing instant when an opening appears which must be driven through with force if success is to be achieved." (E. C. White, Kaironomia p. 13)

Kairos is a season, an opportune time, an opportunity ("window of opportunity"). It is a fixed and definite time. It is a period possessed of certain characteristics. For example, a "season" is a time characterized by a particular circumstance or feature. Thus the time for bringing forth fruit [karpophoros] is the season (kairos) in which the tree bears fruit, in contrast to late autumn, when there is no more fruit.

Kairos does not emphasize a point of time but rather a time space filled with all kinds of possibilities. And so Kairos characteristically means an "opportunity" (and is so translated in some versions -- in  in the NIV and NASB) which represents the best time to do something, the moment when circumstances are most suitable.

From the Moody Bible Institute's "Today in the Word" we read that the idea of kairos...

is not clock time but what one writer calls “kingdom opportunities,” those openings for ministry that often come at inconvenient times; a friend who wants to talk, a child with a problem, the chance to lend a hand to someone in need.  Paul is encouraging us to keep our lives uncluttered so that we can respond when the need arises—because kingdom opportunities can get squeezed out of an overly tight schedule.  (September, 1989)

Paul uses kairos in a manner similar to his use her in Ephesians in the following examples...

So then, while we have opportunity (kairos) let us do good to all men, and especially to those who are of the household of the faith. (Galatians 6:10)