THAT HE WOULD GRANT YOU, ACCORDING TO THE RICHES OF HIS GLORY: hina do (3SAAS) humin kata to ploutos tes doxes autou:  (8; 1:7,18; 2:7; Romans 9:23; Philippians 4:19; Colossians 1:27)

Literally Paul's petition reads

that he may give to you according to the riches of His glory to be strengthened with power

That (2443) (hina) expresses purpose, in this case the purpose for which he is bowing and interceding.

S Lewis Johnson observes that...

there are three “thats” that are important in Paul's prayer. The first one is in verse 16: “That he would grant you, according to the riches of his glory, to be strengthened with might by his Spirit in the inner man.”

Now I know you’re going to say, “Well, must be the that that begins verse 17 must be the second one.” No, in the English translation, that is used, but the little conjunction “that” (hina - 2443) which introduces a purpose clause or at least the substance of the petition, is not used there. So we’ll drop that one, and include it with verse 16, “that he would grant you, according to the riches of his glory, to be strengthened with might by his Spirit in the inner man [to the end] that Christ may dwell in your hearts by faith.”

“That ye, being rooted and grounded in love, may be able to comprehend...” – that’s the second one...

And the third one, in verse 19 in the middle of it, “that ye might be filled with all the fullness of God.”

Each one of these conjunctions,  (hina = 2443) are expressive of the purposes of Paul’s prayer.  Now you’ll notice also that the whole Trinity is involved  (Prayer for Realization of God)

O'Brien comments that...

At the heart of Paul's first petition (see notes Ephesians 1:16;  1:17) for his readers is a request for power. He has already prayed that they might know Gods incomparably great might for them as believers (see notes Ephesians 1:18; 1:19). Now he asks for divine power more directly that God may strengthen them inwardly through his Spirit. If the apostle had urged his Christian readers not to be discouraged on account of his sufferings (see note Ephesians 3:13), then his prayer for them to be strengthened by God's power was in order to meet this need. The resources available to fulfil this confident request are limitless (O'Brien, P. T. The Letter to the Ephesians. W. B. Eerdmans. 1999 or computer version)

Grant (1325) (didomi) means to give as a favor. The grant is based on the decision of the will of the Giver (in this case God) and not on any supposed merit of the recipient.

Wiersbe summarizes Paul's prayer noting that...

There are four requests in Paul’s prayer, but they must not be looked on as isolated, individual petitions. These four requests are more like four parts to a telescope. One request leads into the next one, and so on. He prays that the inner man might have spiritual strength, which will, in turn, lead to a deeper experience with Christ. This deeper experience will enable them to “apprehend” (get hold of) God’s great love, which will result in their being “filled unto all the fullness of God.” So, then, Paul is praying for strength, depth, apprehension, and fullness. (Wiersbe, W: Bible Exposition Commentary. 1989. Victor)

According to - not "out of" (see below). The first is proportionate, the latter is a portion of! There is a "wealth" of difference! Paul used a similar expression to emphasize the limitless power of God in his first prayer that his readers might come to know (quoting from the literal translation)...

what the exceeding greatness of His power to us who are believing, according to (kata) the working of the power of His might (the same might that raised Christ from the dead). (See note Ephesians 1:19)

According (2596) (kata) means in proportion to one's largess! Not stingily. Not just a portion but a proportion! If I am a billionaire and I give you ten dollars, I have given you a portion (very small portion at that) out of my riches. But if I give you ten million dollars, I have given to you according to or more proportionate to my true wealth. The first giver would take it out of His riches and would be like Mr. Rockefeller who used to give his caddy a dime. God is not like Mr. Rockefeller, in either his wealth or generosity!

O'Brien reiterates this great truth writing that...

That glory is Gods radiance or splendour, which conveys the ideas of the perfection of his character and activity. His glory is often conjoined with power (see notes Romans 6:4; Colossians 1:11) and paralleled with his goodness (cf. Ex 33:22 with v. 19). Here this preposition, which Paul often uses in petitions and thanksgivings (see notes Ephesians 1:19; Philippians 4:19), draws attention not simply to the idea of source, thereby signifying out of the wealth of his glory, but also indicates that his giving corresponds to the inexhaustible riches of that glory. It is on a scale commensurate with his glory: he gives as lavishly as only he can...The one to whom he directed his requests gives richly and generously: And my God will fully meet every need of yours in accordance with his riches in glory in Christ Jesus (Phil. 4:19). By formulating his prayer along these lines, the apostle assured his readers that the Father was wholly able to meet their needs. (O'Brien, P. T. The Letter to the Ephesians. W. B. Eerdmans. 1999 or computer version)

John Eadie comments that this phrase...

illustrates the proportion or measurement of the gift, nay, of all the gifts that are comprehended in the apostle's prayer. And it is no exaggeration, for He gives like Himself, not grudgingly or in tiny portions, as if He were afraid to exhaust His riches, or even suspected them to be limited in their contents. There is no fastidious scrupulosity or anxious frugality on the part of the Divine Benefactor. His bounty proclaims His conscious possession of immeasurable resources. He bestows according to the riches of His glory—His own infinite fulness. “That He would give you”— (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

Hughes comments on "according to" observing that...

 to come before the One from whom are all things and to whom are all things (Romans 11:36) makes for great optimism, especially when he is no mere John D. Rockefeller who sometimes gave from his riches, but is rather the One who gives according to his riches — “on the scale and in the style of the wealth of his glory.” Such are the resources from which he strengthens us. (Hughes, R. K.: Ephesians: The Mystery of the Body of Christ. Crossway Books)

Ruth Paxson commenting on "according to" writes...

God is not promising something which He is unable to perform. He estimated His own resources before He promised to bequeath such wealth to His children. God's budget has always been balanced, and there need be no fear of His prodigal program of spending for the salvation and sanctification of believers in His Son. Nothing is unstable in the plan of redemption, for God is not experimenting with men's souls, nor has He left anything to chance. He counted the whole cost of building this wondrous habitation of God long ages before He laid a single living stone upon the foundation, and knew that He was fully able to carry it to completion. In his book In the Heavenlies, Dr. H. A. Ironside unfolds the deep meaning of the words "according to" in a simple illustration: "It does not say 'out of' His riches, but 'according to' His riches. Here is a millionaire to whom you go on behalf of some worthy cause. He listens to you and says, 'Well, I think that I will do a little for you,' and he takes out his pocketbook and selects a ten-dollar bill. Perhaps you had hoped to receive a thousand from him. He has given you 'out of' his riches, but not 'according to' his riches. If he gave you a book of signed blank checks all numbered, and said, 'Take this, fill in what you need,' that would be 'according to' his riches." This is precisely what the King of glory has done for us, as we saw in 1:3. He has given according to the sublime measurement of own immeasurable riches.

Ephesians 3:20 "According to the power that worketh in us."

Perhaps we are quite convinced by now that through our position in Christ we are heirs of God and joint-heirs with Christ. Objectively, we apprehend this fact, and doctrinally we believe it. But our great problem is how to live like heirs. We know what we are; our difficulty is to be what we know. How may we subjectively appropriate this wealth, so that experimentally it is manifested in a consistent walk and a conquering warfare?

God assures us that He has made provision for this experimental realization through the in-working of a resident power. It is the power of a Person Who is none other than God's own Spirit. All that Christ was and did as the incarnate Son was through the power of the Holy Spirit. He promised to send the Holy Spirit to be to the disciples all that He had been to Him. From the day of Pentecost this same Spirit has been in every member of Christ's Body as a mighty power working to make these riches of glory his personal possession. This we shall see more fully as we now begin our study of the prayer petitions. We feel like saying in the words of Dr. Scroggie, "All that we can hope to do is to mark the order in this tumult of holy words."

The trinity of the Godhead work together to make this wealth ours. The riches which the Father provides in the Son are possessed through the Spirit. (The Wealth, Walk and Warfare of the Christian)

Jamieson, et al comments that "according to" means

in abundance consonant (in harmony) to the riches of His glory; not “according to” the narrowness of our hearts.

Riches (4149) (ploutos from pletho = to fill) a plentiful supply of something and in human terms refers to the abundance of possessions exceeding the norm of a particular society (interestingly Paul never uses ploutos with this latter material connotation). Here ploutos refers to God's riches and is a favorite word with Paul in Ephesians to describe the quality of the divine attributes and gifts (cf  2Cor. 8:9; Ephesians 1:7, Ephesians 1:18; Ephesians 2:4, Ephesians 2:7; Ephesians 3:8, here in Eph 3:16; Philippians 4:19; Colossians 1:27)

The riches describe God’s endowment, His infinite wealth and resources. You can’t possibly ask too much.

Paul is saying in essence

“I want you to get your hands on your wealth, realize how vast it is, and start to use it.”

The old gospel hymn says it well...

My Father is rich in houses and lands
He holdeth the wealth of the world in His hands!
Of rubies and diamonds, of silver and gold,
His coffers are full, He has riches untold.”

Our Father's resources are infinite, His repositories are overflowing, His vaults are bottomless.

The treasures of earth are not mine,
I hold not its silver and gold;
But a treasure far greater is mine;
I have riches of value untold. —Hartzler

God's Word promises riches that money cannot buy.

MacDonald adds...

Preachers often point out that there is a difference between the expressions “out of the riches” and according to the riches. A wealthy person might give a trifling amount; it would be out of his riches, but not in proportion to them! Paul asks that God will give strength according to the riches of His perfections. Since the Lord is infinitely rich in glory, let the saints get ready for a deluge! Why should we ask so little of so great a King? When someone asked a tremendous favor of Napoleon it was immediately granted because, said Napoleon, “He honored me by the magnitude of his request.” (MacDonald, W & Farstad, A. Believer's Bible Commentary: Thomas Nelson)

Glory (1391) (doxa) speaks of a manifestation of God's true nature, presence, or likeness. He is glorified when He is allowed to be seen as He really is. To be where God is will be glory. To be what God intended will be glory. To do what God purposed will be glory. The basic idea in the word doxa is that of manifestation. The glory of God is the manifestation of His Being, His character and His acts. The glory of God is what He is essentially. Glory, therefore, is the true apprehension of God or things. The glory of God must mean His unchanging essence.

Would you like a sample of God's glory? Then simply walk out into the countryside on some clear night and observe the starry, starry skies for as David affirms in Psalm 19:1...

The heavens are telling of the glory of God;
And their expanse is declaring the work of His hands.

Now combine this the vast riches and surpassing glory of these starry images with what Job said...

"Behold, these are the fringes of His ways; And how faint a word we hear of Him! But His mighty thunder, who can understand?" (Job 26:14) (Comment: Job's magnificent conclusion is this: How much knowledge of God there is beyond what we can see and hear).

In prayer, it is it is both useful for ourselves and glorifying to God to recognize His bountifulness—to remember that He gives to as a the riches of Kings! I love what John Newton wrote that relates to this idea...

Thou art coming to a King,
Large petitions with thee bring;
For His grace and power are such,
None can ever ask too much.

TO BE STRENGTHENED WITH POWER THROUGH HIS SPIRIT: dunamei krataiothenai (APN) dia tou pneumatos autou:  6:10; Job 23:6; Psalms 28:8; 138:3; Isaiah 40:29-31; 41:10; Zechariah 10:12; Matthew 6:13; 2 Corinthians 12:9; Philippians 4:13; Colossians 1:11; 2 Timothy 4:17; Hebrews 11:34)

S Lewis Johnson observes that the first petition is a petition for empowerment.

It is notable that Paul's prayers are almost always for the spiritual welfare of others -- a good pattern for imitators of Paul to follow.

To be strengthened (2901) (krataioo from krataios = strong <> see study of root kratos) means to be empowered, to be increased in vigor,  to strengthen with the implied meaning of to establish (active voice), to grow strong (active voice), to be made strong (passive voice), to be braced (as when the Gulf Coast states in the US "brace" for the onrushing Category 5 hurricane!), to be invigorated, to be  fortified (I like that word for it pictures the saint in a "spiritual fort"). Note that all the NT uses are in the passive voice.

Krataioo refers to strength or might, but especially that which is manifested.

As discussed below krataioo in this verse means  to be shown to be strong, to be shown to be mighty.

The passive voice indicates the strengthening to our inner man comes not from man himself but from God's indwelling Spirit.

TDNT writes that krataioo...

means “to make strong,” occurs 54 times in the Septuagint (LXX) (Jdg. 3:10; Ruth 1:18; 1Sa 4:9; 23:16; 30:6; 2Sa 1:23; 2:7; 3:1; 10:11, 12; 11:23, 25; 13:14; 22:18; 23:3; 1Ki. 20:22-23, 25; 2 Ki. 3:26; 12:6 -7, 12, 14; 22:6; 1 Chr. 21:4; 2 Chr. 21:4; 23:1; 34:8; 35:22; Ezra 6:22; 7:28; Neh. 2:18; 6:9; Job 36:19, 22; Ps. 9:19; 27:14; 31:24; 38:19; 64:5; 69:4; 74:13; 80:15, 17; 89:13; 103:11; 105:4, 24; 117:2; 139:6, 17; 142:6; Lam. 1:16; Dan. 4:36; 5:20). In the NT we find only the passive “to become strong.” In Lk. 1:80; 2:40 it denotes childhood growth. In 1 Cor. 16:13, with andrízesthe, the exhortation is to “be strong” (cf. 2 Sa 10:12 "Be strong, and let us show ourselves courageous for the sake of our people and for the cities of our God; and may the LORD do what is good in His sight."). Eph. 3:16 traces such strengthening to the inward operation of the Holy Spirit (cf. 2 Sa 22:3). (Kittel, G., Friedrich, G., & Bromiley, G. W.  Theological Dictionary of the New Testament. Eerdmans)

NIDNTT writes that krataioo means...

to make strong, to take courage, to gain the upper hand over. krataioo is used in the Lucan birth narratives to describe the child Jesus growing and becoming strong in spirit (Lk. 1:80) and wisdom (Lk 2:40). Otherwise the word is not common in the NT. It clearly refers to manly strength in 1 Cor. 16:13, which is a quotation (cf. Ps 31:24; 2 Sa 10:12); and has a metaphorical sense in Eph. 3:16; in Gnostic terminology, the inner man is expected to be strengthened with might. (Brown, Colin, Editor. New International Dictionary of NT Theology. 1986. Zondervan)

Here are the other 3 NT uses of krataioo..

Lu 1:80 - And the child continued to grow and to become strong (to become strong and healthy, with the implication of physical vigor) in spirit, and he lived in the deserts until the day of his public appearance to Israel.

Lu 2:40 - The Child continued to grow and become strong, increasing in wisdom; and the grace of God was upon Him.

1Cor 16:13 - Be on the alert, stand firm in the faith, act like men, be strong. (Comment: Krataioo is frequently used in the NT to denote inner, spiritual growth. As in Eph 3:16, krataioo is also in the passive voice, which literally means “be strengthened.” In this context the implication is that the believer is to be sufficiently strong as to be able to dominate any evil influence [world, flesh, devil].

In the physical world one might lift weights and so strengthen themselves, but in the spiritual world, believers cannot strengthen ourselves for that task belongs solely to the Lord! However, don't forget that believers do have a role/responsibility in this spiritual strengthening -- we are not just to "Let go and let God". The believer's "job" is to submit [yield, surrender] himself or herself to God's Spirit [believers can resist, quench and grieve the Spirit] in order that He can strengthen us. We can only “be [passive voice] strong in the Lord, and in the strength of His might” (see note Ephesians 6:10), and “be [passive voice] strong in the grace that is in Christ Jesus” (see note 2 Timothy 2:1).

John Eadie comments that Paul...

had likened the Ephesian Christians to a temple, and in harmony with such a thought he prays that the living stones in that fabric may be strengthened, so that the building may be compact and solid.  (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

Barnes writes that "to be strengthened with power" means...

to give you abundant strength to bear trials; to perform your duties; to glorify his name...See [Ro 7:22]. The body needs to be strengthened every day. In like manner the soul needs constant supplies of grace. Piety needs to be constantly invigorated, or it withers and decays. Every Christian needs grace given each day to enable him to bear trials, to resist temptation, to discharge his duty, to live a life of faith. (Albert Barnes. Barnes NT Commentary)

Wayne Barber explains that krataioo...

means "made mighty." It is the Greek word krataioo. Some Greek verbs end in an "o" but this verb ends in two o’s which conveys the thought of something beyond just being "strengthened." It means "to be shown to be strong, to be shown to be mighty." It is almost the same thing that Paul prays in Philippians. The idea then is that you are to get what is on the inside of you to the outside so that you might be shown to be strong...Is there a difference between might and power?" Oh, yes. The word "power" here is the word dunamis. That word means "to be able to do something, be capable." Basically Paul is saying,

"I want that which is inside of you to get on the outside of you. I want people to look at you as you live your Christian life and let them see that you have a divine ability that is operating inside of you. I want it to be more than just what you say. I am praying that it will be in how that you live."

The assignment to do the strengthening is not in God the Son, it is God the Spirit. The Spirit of God comes into a man the moment he becomes a Christian. Now, you are not living life alone. You may be acting like it, but you are not. If you are trying to fight your problems by yourself, if you are trying to figure them out on your own, if you are not coming to the Word, letting the Holy Spirit of God enable you and reveal to you the things of God, then no wonder you are confused. You have a divine partner living in you, and He is in you to strengthen you with power so that you have an ability that you didn’t have before. If you will learn to tap into Him, then you will begin to learn to live in the reality of His presence....

Now understand something. He is not praying that they will get these riches. They already have them. He is praying that they be strengthened according to these riches. He is saying,

"You’ve got them. Now be strengthened by that which you have. Live in it. Live out of it."

Folks, we have a reservoir of riches of wealth, spiritually, which God has given us in the Lord Jesus Christ. Paul intensely says, "Oh, God, don’t let them walk out with heads filled with information. God, let them walk out understanding they have these riches. Let them be strengthened in the inner man with power. Let these riches be a part of the source of their strength in their walk."

You may find out this week that you have lost your job. You may find out this week that someone has done you wrong. Where are you going to be strengthened? Friend, Paul is saying you know something about your salvation. When you run back to the Lord Jesus Christ, in Him is the reservoir of what you are looking for. Let the Spirit of God with power strengthen you in the inner man. Let these truths so get down inside of your life that you become different. All of a sudden what you have inside of you begins to work inside of you. All of a sudden people see a difference in your life. You are doing things and you are living in a way that is on a higher plane than what you lived before. In other words, don’t just sit and soak. Grab hold of the fact that you have got all the wealth that ever could be, spiritually, in the Lord Jesus Christ. Learn how to tap into it. Learn how to draw it out. It is in your account. It is in your name. The Lord Jesus lives in you. When you have your problems, run to Him.

Learn to be strengthened according to the riches that He has given you in Christ Jesus. (Ephesians 3:14: A Prayer for Fullness - 1)

Boice explains Paul's first request for the believers to be strengthened internally through the Spirit writing that...

Paul has been talking about suffering, and this is probably why he begins his prayer with a request that the believers at Ephesus might be strengthened by God’s Spirit. None of us show much of the manifold wisdom of God in easy days. It is in suffering that the grace of God is manifested. But who has strength for suffering? We do not choose suffering. We shrink from it. Like Christ in the garden we inevitably draw back and ask that, if it is possible, this cup might pass from us. If we are to show God’s wisdom in such times, it must be by God’s strength. He must send his angels to minister to us.

Still, it is not only in times of suffering that we need to be strengthened. We need strength every day of our lives and in every circumstance.

Is it temptation? We need strength to resist it and be victorious to the glory of God.

Is it a tough moral choice at work? We need strength to do the right thing so that Jesus, whom we serve, might be honored.

Is it witnessing? We need strength to speak the truth regardless of what the world may think of us for speaking it. When Jesus prayed for God to send the Comforter or Holy Spirit to be with his disciples it was this he chiefly had in mind. The word parakletos (“comforter,” “counselor,” or “advocate”) means “one called alongside to help.” The Holy Spirit helps us do the right thing in difficult circumstances. (Boice, J. M.: Ephesians: An Expositional Commentary)

When Martin Luther was summoned to Worms to recant his 95 Theses he wrote...

“May the Lord Jesus strengthen me.”

Power (1411) (dunamis from dunamai = to be able, to have power) (Click word study of dunamis) power especially achieving power. It refers to intrinsic power or inherent ability, the power or ability to carry out some function, the potential for functioning in some way, the power residing in a thing by virtue of its nature.  Dunamis is the word generally used by Paul of divine energy.

Note that words derived from the stem duna— all have the basic meaning of “being able,” of “capacity” in virtue of an ability. Duna- is the root for English words like dynamic, dynamo, dynamite, etc.

A stick of dynamite has power but the fuse has to be lit for the inherent power to be manifest...so too with God's dunamis. Earlier Paul had prayed that the saint's be enlightened to the truth that they possess this surpassingly great power, the same (dunamis) power which effected the miraculous resurrection of our Redeemer (See notes Ephesians 1:19; 1:20)

Paul prays these believers be made mighty with power, or dunamis, the ability to do that which we could never have done before, the capacity, the divine ability to live a life on a higher plane.

Dunamis conveys the idea of effective, productive energy, rather than that which is raw and unbridled. Where is this inherent power derived from? Through the working of God's Holy Spirit. And where is the sphere of operation of this enabling power? in the inner man.

Paul is praying for every saint (not some special class of elite so-called "spiritual" Christians) to possess genuine spiritual power, which ultimately is a mark of every believer who submits to God's Word and His Spirit (Corollary question - Do you lack spiritual power in your Christian life? Then do a simple inventory -- Look at your "obedience quotient" - immediate or delayed [= disobedience] or non-existent, Look at your intake of sound doctrine vs "religious literature" [e.g. Christian novels, magazines, even devotionals, etc] vs only secular sources [R rated movies, fowl language on TV, "premium channels" on Cable, etc] and finally look at your surrender to to the Spirit - sweet surrender, partial and halting, willfully resistant to His voice.)

Note that in this context this (dunamis) power is not necessarily the power to perform spectacular, sensational miracles (which is the predominant meaning of dunamis in its uses in the gospels - eg, see Mt 11:20, 23, 13:54, 58, etc), but the spiritual power necessary to live as mature, stable, wise Christians in the midst of a crooked and perverse generation. It is by dunamis power that a believer is enabled to say "Yes" to his Lord and "No" to his flesh. Daily victory of sin (the world, the flesh and devil) is one of the greatest "miracles" a believer can experience.

Dunamis is the implied ability or capacity to perform. It conveys the idea of effective, productive energy, rather than that which is raw and unbridled.

Dunamis is the potential for functioning in some way (power, might, strength, ability, capability).

Sometimes dunamis is used to represent an entity or being that functions with remarkable power, especially being used to describe angel as powers (eg, see notes Romans 8:38, Ephesians 6:12)

There is an instructive use of dunamis later in 2Timothy where Paul describes men...

holding to a form of godliness, although they have denied its power; and avoid such men as these. (See note 2 Timothy 3:5) (Comment: The point is that the so-called godliness of these men is a sham and devoid of any real power (dunamis) to break the power of sin. Those who practice such deception enjoy the external expressions of evangelical worship to be amenable to their lifestyles but they are violently at odds with the gospel’s internal effects of subduing sin and nurturing holiness. They lack the inherent ability or capability, the dunamis, because they lack the indwelling Spirit Who strengthens with power as Paul prays in Ephesians 3:16. The corollary is that those who possess the indwelling Spirit and divine dunamis have the inherent ability to wage victorious battle with the three mortal enemies, the world, the flesh and the devil, all seeking to turn us from God and unto self with its consequent ungodly, unholy attitudes and actions. One can readily see the importance of praying for believers to be strengthened with dunamis power through the Spirit in their inner man - see Ephesians 3:16)

William MacDonald comments on Paul's reminder to Timothy of his access to God's "dunamis" writing that...

"Unlimited strength is at our disposal. Through the enabling of the Holy Spirit, the believer can serve valiantly, endure patiently, suffer triumphantly, and, if need be, die gloriously."

MacDonald quotes F B Meyer

"It is power. It is His power. It is great power; nothing less would suffice. It is exceeding great power, beyond the furthest cast of thought.”

This is the power which God used in our redemption, which He uses in our preservation, and which He will yet use in our glorification. Lewis Sperry Chafer writes: Paul wants to impress the believer with the greatness of the power which is engaged to accomplish for him everything that God has purposed according to His work of election, predestination and sovereign adoption." (MacDonald, W & Farstad, A. Believer's Bible Commentary: Thomas Nelson)

Note that in his letter to the Ephesians Paul did not pray that believers might be given divine power but that they might be aware of the divine power they already possessed. (See notes Ephesians 1:18; 1:19; 1:20). Through Christ we have the resource of God’s own supernatural power, the very power (dunamis) He used to raise Christ from the dead. It is of utmost importance to understand that God does not provide His power for us to misappropriate for our own purposes. He provides His power to accomplish His purposes through us. When our trust is only in Him, and our desire is only to serve Him, He is both willing and “able to do exceeding abundantly beyond all that we ask or think, according to the power that works within us” (see note Ephesians 3:20).

Although God promises us and provides us with His dunamis power, we must learn wait upon His timing (Acts 1:8) and also be willing to humble ourselves that His power may be perfected in us (2Cor 12:9). Note that Jesus Himself had at least in one sense the same power available to believers today (see Lu 4:1,14,18 ...God anointed Him with the Holy Spirit and with power)

Barclay writes that dunamis...

can be used of any kind of extraordinary power. It can be used of the power of growth, of the powers of nature, of the power of a drug, of the power of a man’s genius. It always has the meaning of an effective power which does things and which any man can recognize. (Barclay, W: The Daily Study Bible Series, Rev. ed. Philadelphia: The Westminster Press)

An Illustration of Strength in the Lord...

In 1934, when Adolf Hitler summoned German church leaders to his Berlin office to berate them for insufficiently supporting his programs, he was surprised when Pastor Martin Niemoller stood up to him. That evening his Gestapo raided Niemoller’s rectory, and a few days later a bomb exploded in his church. He was later arrested and placed in solitary confinement. Dr. Niemoller’s trial began on February 7, 1938. That morning, a green-uniformed guard escorted the minister from his prison cell and through a series of underground passages toward the courtroom. Niemoller was overcome with terror and loneliness. What would become of him? Of his family? His church? The guard’s face was impassive, but as they exited a tunnel to ascend a final flight of stairs, Niemoller heard a whisper. At first he didn’t know where it came from, for the voice was soft as a sigh. Then he realized that the officer was breathing into his ear the words of Proverbs 18:10:

“The name of the Lord is a strong tower
The righteous run to it and are safe.”

Niemoller’s fear fell away, and the power of that verse sustained him through his trial and his years in Nazi concentration camps.

Through (1223) (dia) refers to the instrument by which the strengthening with power is effected, in this case the Holy Spirit). In other words this divine empowering will be effected through God's Spirit. The agency of the Spirit in dispensing divine power is in line with other New Testament teaching where the Spirit and power are intimately linked (Acts 1:8; see notes Romans 1:4; 1; Romans 15:19; 1Cor 2:4; 1Thessalonians 1:5).

Spirit (4151) (pneuma) in context refers to the Holy Spirit not man's inner spirit. The dunamis (dynamic) power is communicated to us by the Spirit Who is our dynamo, residing in every believer and working through us. Although His name is not specifically mentioned we see His working in Philippians 2 where Paul records...

So then, my beloved, just as you have always obeyed, not as in my presence only, but now much more in my absence, work out your salvation with fear and trembling; for it is God who is at work in you, both to will and to work for His good pleasure. (See notes Philippians 2:12; 2:13)

John Eadie comments that...

The Spirit of God is the agent in this process of invigoration. That Spirit is God's, as He bears God's commission and does His work. He has free access to man's spirit to move it as He may, and it is His peculiar function in the scheme of mercy to apply to the heart the spiritual blessings provided by Christ. (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

It is always good to remember that Jesus performed His ministry on earth in the power of the Spirit (see verses below), and this is the only resource we have for Christian living today.

Luke 4:1 And Jesus, full of the Holy Spirit, returned from the Jordan and was led about by the Spirit in the wilderness...14 And Jesus returned to Galilee in the power (dunamis - the inherent ability) of the Spirit; and news about Him spread through all the surrounding district.

Acts 10:38 "You know of Jesus of Nazareth, how God anointed Him with the Holy Spirit and with power, and how He went about doing good (implicit that He did good empowered by the Spirit), and healing all who were oppressed by the devil; for God was with Him.

 IN THE INNER MAN: eis ton eso anthropon:  (Jeremiah 31:33; Romans 2:29; 7:22; 2 Corinthians 4:16; 1 Peter 3:4)

In (eis) marks out the destination of the gift. It is not simply “in reference to" or "for" but it denotes or implies that the dunamis comes from an external source, and enters into the inner man. The inner man is the sphere (many commentators favor the preposition "eis" in this case to point more to the sphere) in which the strengthening is to take place.

Eadie writes that...

The “inner man” is that portion of our nature which is not cognizable by the senses, and does not consist of nerve, muscle, and organic form, as does the outer man. In the physiology of the seventh chapter of the Epistle to the Romans, it (inner man) is not the soul—psuche—in its special aspect of vital consciousness, but it is more connected with mind—nous, and stands in contrast not exactly to sarx, as representing generally depraved humanity, but to that sensuous nature which has action and reaction in and from the members... it is the sphere in which (spiritual) renewal takes effect—our intellectual and spiritual nature personified...

And this strength is imparted to the “inner man” by the Spirit's application of those truths which have a special tendency to cheer and sustain. He impresses the mind with the idea of the changeless love of Christ, and the indissoluble union of the believing soul to Him; with the necessity of decision, consistency, and perseverance; with the assurance that all grace needed will be fully and cheerfully afforded; and with the hope that the victory shall be ultimately obtained. Rom. 15:13; 2 Tim. 1:7. This operation of the Spirit imparts such courage and energy as appear like a species of spiritual omnipotence. (John Eadie, D., LL.D. The Epistle of St Paul to the Ephesians)

Paxson writes...

 Is there any greater need in the Christian's life than to be made strong and with a power outside of himself? How often he feels that he is going backward rather than forward. He is conscious of weakness, failures, defeats, and backslidings that are well-nigh overpowering. More than once he cries out in anguish of spirit,

"Is it worth while to try to keep on? I just have not the strength for this conflict."

Nor has he, and God rejoices whenever a child of His comes to the end of himself and acknowledges his own utter impotency, for then God can begin to work. The Pentecost promise was for power. We are to be made strong with power through a Person.

"By His Spirit." The Holy Spirit who worked for us to implant life now works in us to impart power. He lives within us to strengthen and energize with divine might and by a definite and continuous process. The life bestowed by the Spirit through rebirth is to be realized in fulness through renewal.

"In the inner man." Into