Colossians 1
Introduction
Colossians 1 contains one of the New Testament's central Christological passages (vv. 15-20). Paul opens with his customary greeting and thanksgiving, commending the Colossians for the faith and love that Epaphras reported to him, and then transitions into a sustained prayer for their spiritual growth. The chapter builds toward the Christ hymn, which declares Christ's supremacy over all creation and his role as the agent and goal of all that exists. This hymn is not merely an abstract theological statement but is carefully aimed at the "Colossian heresy" -- a syncretistic false teaching that threatened to diminish the sufficiency and supremacy of Christ by supplementing him with angelic mediators, mystical experiences, and human philosophy.
The second half of the chapter applies the cosmic reconciliation of the hymn to the Colossians' own experience: they who were once alienated from God have now been reconciled through the death of Christ. Paul then turns to his own apostolic ministry, describing his suffering on behalf of the church and his commission to make known the mystery that had been hidden for ages -- "Christ in you, the hope of glory." The chapter thus moves from the cosmic to the personal, from the work of Christ in the universe to the work of Christ in the believer, establishing the theological foundation upon which the rest of the letter will build its practical exhortations and its warnings against false teaching.
Greeting (vv. 1-2)
1 Paul, an apostle of Christ Jesus by the will of God, and Timothy our brother, 2 To the saints and faithful brothers in Christ at Colossae: Grace and peace to you from God our Father.
1 Paul, an apostle of Christ Jesus by the will of God, and Timothy our brother, 2 to the saints and faithful brothers in Christ at Colossae: grace and peace to you from God our Father.
Notes
Paul's greeting follows the standard form of his letters, but every element carries theological weight. He identifies himself as an ἀπόστολος ("apostle") of Christ Jesus διὰ θελήματος Θεοῦ ("by the will of God"). Since Paul had never visited Colossae personally (Colossians 2:1), his authority over this church rests not on personal acquaintance but on his divine commission. Timothy is named as co-sender but called ἀδελφός ("brother"), not "apostle" -- a distinction Paul maintains consistently.
The recipients are described as ἁγίοις καὶ πιστοῖς ἀδελφοῖς ἐν Χριστῷ ("saints and faithful brothers in Christ"). The word "saints" does not denote moral perfection but rather their status as those set apart by God. The phrase ἐν Κολοσσαῖς ("at Colossae") locates them geographically, while ἐν Χριστῷ ("in Christ") locates them spiritually. Colossae was a small city in the Lycus Valley of Phrygia, overshadowed by its neighbors Laodicea and Hierapolis. By Paul's day it was the least significant of the three, yet it received significant theological letters in the New Testament.
The greeting χάρις ὑμῖν καὶ εἰρήνη ("grace and peace to you") fuses the standard Greek greeting (chairein, "greetings") with the Hebrew blessing of shalom ("peace"). Some manuscripts add "and the Lord Jesus Christ" after "God our Father," harmonizing with Paul's other letters, but the shorter reading is likely original.
Thanksgiving and Prayer (vv. 3-14)
3 We always thank God, the Father of our Lord Jesus Christ, when we pray for you, 4 because we have heard about your faith in Christ Jesus and your love for all the saints -- 5 the faith and love proceeding from the hope stored up for you in heaven, of which you have already heard in the word of truth, the gospel 6 that has come to you. All over the world this gospel is bearing fruit and growing, just as it has been doing among you since the day you heard it and truly understood the grace of God. 7 You learned it from Epaphras, our beloved fellow servant, who is a faithful minister of Christ on our behalf, 8 and who also informed us of your love in the Spirit.
9 For this reason, since the day we heard about you, we have not stopped praying for you and asking God to fill you with the knowledge of His will in all spiritual wisdom and understanding, 10 so that you may walk in a manner worthy of the Lord and may please Him in every way: bearing fruit in every good work, growing in the knowledge of God, 11 being strengthened with all power according to His glorious might so that you may have full endurance and patience, and joyfully 12 giving thanks to the Father, who has qualified you to share in the inheritance of the saints in the light. 13 He has rescued us from the dominion of darkness and brought us into the kingdom of His beloved Son, 14 in whom we have redemption, the forgiveness of sins.
3 We give thanks to God, the Father of our Lord Jesus Christ, always praying for you, 4 since we heard of your faith in Christ Jesus and the love that you have for all the saints, 5 because of the hope that is stored up for you in the heavens, which you previously heard about in the word of truth, the gospel 6 that has come to you. Just as in all the world it is bearing fruit and growing, so also among you from the day you heard it and came to know the grace of God in truth -- 7 just as you learned it from Epaphras, our beloved fellow slave, who is a faithful servant of Christ on our behalf, 8 and who made known to us your love in the Spirit.
9 For this reason, from the day we heard about you, we have not stopped praying for you and asking that you may be filled with the knowledge of his will in all spiritual wisdom and understanding, 10 so that you may walk in a manner worthy of the Lord, fully pleasing to him: bearing fruit in every good work and growing in the knowledge of God, 11 being empowered with all power according to the might of his glory, for all endurance and patience with joy, 12 giving thanks to the Father who qualified you for a share in the inheritance of the saints in the light. 13 He rescued us from the authority of the darkness and transferred us into the kingdom of the Son of his love, 14 in whom we have redemption, the forgiveness of sins.
Notes
Paul's thanksgiving section reveals crucial information about a church he has never visited. The triad of faith, love, and hope (vv. 4-5) echoes 1 Corinthians 13:13 and 1 Thessalonians 1:3, but here Paul arranges them differently. Faith and love are described as διὰ τὴν ἐλπίδα ("because of the hope") -- that is, the Colossians' faith and love are grounded in and motivated by their eschatological hope. This hope is not wishful thinking but a certain expectation ἀποκειμένην ὑμῖν ἐν τοῖς οὐρανοῖς ("stored up for you in the heavens"), like a treasure deposited in a secure vault (compare 1 Peter 1:4).
The gospel is described with two dynamic participles in verse 6: καρποφορούμενον ("bearing fruit") and αὐξανόμενον ("growing"). These organic metaphors present the gospel not as a static message but as a living force that produces results and expands wherever it goes. The same two words will reappear in verse 10 applied to believers, creating a parallel: as the gospel bears fruit and grows in the world, so believers are to bear fruit and grow in their knowledge of God.
Epaphras is introduced in verse 7 as the one who brought the gospel to Colossae. Paul calls him ἀγαπητοῦ συνδούλου ("beloved fellow slave") -- the compound σύνδουλος is distinctive to Colossians and places Epaphras alongside Paul as a servant of Christ, not beneath him. Paul's endorsement of Epaphras is not incidental; it subtly affirms that the gospel the Colossians received from Epaphras is the authentic gospel, not the distorted version being promoted by the false teachers.
Paul's prayer (vv. 9-14) is structured around one main request with cascading results. The central petition is that they be πληρωθῆτε τὴν ἐπίγνωσιν τοῦ θελήματος αὐτοῦ ("filled with the knowledge of his will"). The word ἐπίγνωσις ("knowledge") is the intensified form of γνῶσις ("knowledge"), meaning "full knowledge" or "deep knowledge." This may be a deliberate counter to the false teachers who promised a superior, esoteric knowledge; Paul prays that the Colossians already have genuine, full knowledge from God.
The purpose of this knowledge is practical: to περιπατῆσαι ἀξίως τοῦ Κυρίου ("walk in a manner worthy of the Lord"). The verb περιπατέω ("to walk") is the standard Pauline metaphor for daily conduct. Four participles then spell out what this worthy walk looks like: bearing fruit, growing, being strengthened, and giving thanks.
Verses 12-14 transition from prayer to proclamation. The Father ἱκανώσαντι ("qualified") believers -- the verb means "to make sufficient, to render competent." God has made believers fit for something they could never deserve on their own: τὴν μερίδα τοῦ κλήρου τῶν ἁγίων ἐν τῷ φωτί ("a share in the inheritance of the saints in the light"). The language of "inheritance" and "lot" echoes the allotment of the Promised Land to Israel's tribes (see Joshua 14:2), reimagined now as a spiritual inheritance belonging to all believers.
The rescue described in verse 13 is dramatic: God ἐρρύσατο ("rescued/delivered") us from τῆς ἐξουσίας τοῦ σκότους ("the authority of the darkness") and μετέστησεν ("transferred") us into the kingdom of his beloved Son. The verb "transferred" was used in the ancient world for the deportation of a conquered population to a new territory -- but here it is reversed: God has deported believers out of the realm of darkness and resettled them in the kingdom of his Son. The phrase τοῦ Υἱοῦ τῆς ἀγάπης αὐτοῦ ("the Son of his love") is a Semitic construction meaning "his beloved Son."
Verse 14 gathers these threads: in this Son ἔχομεν τὴν ἀπολύτρωσιν, τὴν ἄφεσιν τῶν ἁμαρτιῶν ("we have redemption, the forgiveness of sins"). The word ἀπολύτρωσις ("redemption") comes from the slave market -- it means the price paid to release a slave. The second phrase is epexegetical: redemption is defined as the forgiveness of sins. The Textus Receptus adds "through his blood," harmonizing with Ephesians 1:7, but the shorter reading is likely original. The mention of redemption and forgiveness sets the stage for the great hymn that follows, which will explain the cosmic basis for this personal salvation.
The Supremacy of Christ (vv. 15-20)
15 The Son is the image of the invisible God, the firstborn over all creation. 16 For in Him all things were created, things in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities. All things were created through Him and for Him. 17 He is before all things, and in Him all things hold together. 18 And He is the head of the body, the church; He is the beginning and firstborn from among the dead, so that in all things He may have preeminence. 19 For God was pleased to have all His fullness dwell in Him, 20 and through Him to reconcile to Himself all things, whether things on earth or things in heaven, by making peace through the blood of His cross.
15 He is the image of the invisible God, the firstborn over all creation, 16 because in him all things were created, in the heavens and on the earth, the visible and the invisible, whether thrones or dominions or rulers or authorities -- all things have been created through him and for him. 17 And he himself is before all things, and in him all things hold together. 18 And he himself is the head of the body, the church. He is the beginning, the firstborn from the dead, so that he might come to have first place in everything, 19 because in him all the fullness was pleased to dwell, 20 and through him to reconcile all things to himself, making peace through the blood of his cross -- through him, whether things on the earth or things in the heavens.
Notes
This passage (vv. 15-20) is widely recognized as a pre-Pauline hymn or poetic composition that Paul either authored or inherited and shaped for his purposes. Its elevated style, rhythmic structure, and concentrated Christological content set it apart from the surrounding prose. The hymn divides into two stanzas: the first (vv. 15-17) celebrates Christ's supremacy in creation; the second (vv. 18-20) celebrates his supremacy in redemption. The two stanzas are connected by parallel structures: each begins with a relative pronoun referring to Christ, each uses the title "firstborn," and each culminates in a statement about "all things."
The hymn opens with two key Christological titles: εἰκὼν τοῦ Θεοῦ τοῦ ἀοράτου ("image of the invisible God"). The word εἰκών ("image") is stronger than a mere reflection or likeness. In Hellenistic philosophy, an image could participate in the reality it represented; in the Old Testament, humanity was created in the "image" of God (Genesis 1:26-27). But what Adam was derivatively, Christ is essentially: the perfect, exact representation of the invisible God. The paradox is deliberate -- how can the invisible God have an image? Only because the Son is not a created copy but the eternal manifestation of what God is. This parallels John 1:18 ("No one has ever seen God; the only begotten God... has made him known") and Hebrews 1:3 ("the exact representation of his being").
The title πρωτότοκος πάσης κτίσεως ("firstborn over all creation") has been debated throughout church history. The word πρωτότοκος ("firstborn") can mean either "first in time" (the first one born) or "first in rank" (the one with the rights and privileges of the firstborn). In the Old Testament, "firstborn" frequently denotes supremacy and preeminence rather than chronological priority. Israel is called God's "firstborn" (Exodus 4:22) though not the first nation created. David is called "firstborn" (Psalm 89:27) though he was the youngest of Jesse's sons. The genitive πάσης κτίσεως ("of all creation") is best understood as a genitive of relation or comparison -- "firstborn with respect to all creation," meaning that Christ holds the rank of supremacy over all created things. Verse 16 confirms this with the explanatory ὅτι ("because"): the reason he is firstborn over creation is that he is the agent by whom all things were created. The Creator cannot be part of the creation.
Verse 16 makes a comprehensive claim about Christ's creative work. Three prepositions define his role: all things were created ἐν αὐτῷ ("in him," the sphere), δι᾽ αὐτοῦ ("through him," the agent), and εἰς αὐτόν ("for him," the goal). This threefold prepositional formula echoes language Paul uses elsewhere of God the Father (compare Romans 11:36: "from him and through him and to him are all things"). By applying this language to Christ, Paul is making an implicit claim to Christ's deity.
The catalogue of invisible powers -- θρόνοι ("thrones"), κυριότητες ("dominions"), ἀρχαί ("rulers"), ἐξουσίαι ("authorities") -- is likely aimed directly at the Colossian heresy, which apparently included the veneration of angelic beings. Paul's point is emphatic: whatever spiritual powers the false teachers want to honor, Christ created them. They owe their existence to him. This list reappears in Colossians 2:10 and Colossians 2:15, where Christ is declared head over every ruler and authority and is said to have triumphed over them at the cross.
Verse 17 adds two further claims. First, αὐτός ἐστιν πρὸ πάντων ("he himself is before all things") -- the present tense "is" (not "was") combined with the preposition "before" asserts Christ's eternal pre-existence. Second, τὰ πάντα ἐν αὐτῷ συνέστηκεν ("in him all things hold together"). The verb συνέστηκεν is a perfect tense of συνίστημι, meaning "to stand together, to cohere, to be held together." Christ is not only the Creator but the Sustainer -- the one who maintains the coherence and order of the universe at every moment. Without him, all things would fly apart into chaos.
The second stanza (v. 18) opens with a parallel to verse 15: αὐτός ἐστιν ἡ κεφαλὴ τοῦ σώματος, τῆς ἐκκλησίας ("he himself is the head of the body, the church"). The word κεφαλή ("head") here carries the sense of authority and rule, not merely source or origin. In Ephesians 1:22-23 the same metaphor is developed more fully; here the emphasis falls on Christ's absolute authority over the church. The apposition — "the body, the church" — is characteristic of Paul's ecclesiology: the church is not an institution alongside Christ but his own living body.
Christ is then called ἀρχή ("beginning") and πρωτότοκος ἐκ τῶν νεκρῶν ("firstborn from the dead"). Just as he is firstborn over the old creation (v. 15), he is firstborn from the dead -- the inaugurator of the new creation through his resurrection. The purpose clause ἵνα γένηται ἐν πᾶσιν αὐτὸς πρωτεύων ("so that he might come to have first place in everything") summarizes the entire hymn. The verb πρωτεύω ("to be first, to have preeminence") appears only here in the New Testament. Christ's supremacy is not one claim among many but the central claim of the passage: he must hold first place in absolutely everything.
Verse 19 introduces the concept of πλήρωμα ("fullness"): ἐν αὐτῷ εὐδόκησεν πᾶν τὸ πλήρωμα κατοικῆσαι ("in him all the fullness was pleased to dwell"). The subject of "was pleased" is debated -- it could be "God" (understood from context) or "all the fullness" itself (treated as the grammatical subject). The word πλήρωμα will be made explicit in Colossians 2:9: "in him the whole fullness of deity dwells bodily." The verb κατοικῆσαι ("to dwell, to take up permanent residence") implies more than a temporary sojourn — the divine fullness has taken up permanent residence in Christ. This is a decisive refutation of any system that distributes divine fullness across multiple intermediaries.
Verse 20 is the climax: through Christ, God determined ἀποκαταλλάξαι τὰ πάντα εἰς αὐτόν ("to reconcile all things to himself"). The compound verb ἀποκαταλλάσσω ("to reconcile completely") is found only in Paul (here and Ephesians 2:16). The means of this reconciliation is εἰρηνοποιήσας διὰ τοῦ αἵματος τοῦ σταυροῦ αὐτοῦ ("making peace through the blood of his cross"). The verb εἰρηνοποιέω ("to make peace") appears only here in the New Testament. The juxtaposition of "peace" and "blood of the cross" is startling -- peace is not achieved through negotiation or compromise but through violent, sacrificial death. The scope extends to "all things, whether things on the earth or things in the heavens." The cosmic disorder introduced by sin affects not only humanity but the entire created order, and Christ's reconciling work is correspondingly cosmic in scope.
Interpretations
The phrase "firstborn over all creation" (v. 15) has been at the center of Christological debate since the early centuries of the church. In the fourth century, the Arians argued that πρωτότοκος ("firstborn") proves that Christ was the first and greatest created being -- the highest of all creatures, but a creature nonetheless. The Council of Nicaea (AD 325) and the broader orthodox tradition rejected this reading, arguing that "firstborn" in its biblical usage denotes rank and preeminence, not temporal origin. The immediately following verse (v. 16) is the decisive counterargument: if "all things" were created in, through, and for Christ, then Christ himself cannot be one of the "all things" that were created. The title "firstborn" places Christ over creation as its sovereign ruler, not within creation as its first member. This remains the standard reading across Reformed, Lutheran, Anglican, and other Protestant traditions. Jehovah's Witnesses and some Unitarian groups continue to read "firstborn" as "first-created," but this requires inserting the word "other" into verse 16 ("all other things were created"), which has no basis in the Greek text.
The meaning of πλήρωμα ("fullness") in verse 19 has also been much discussed. In later Gnostic systems, "pleroma" was a technical term for the totality of divine emanations that filled the gap between the transcendent God and the material world. Some scholars believe that Paul (or the hymn's original author) is using the term polemically -- co-opting a concept that the Colossian false teachers may have been employing and insisting that the entire divine fullness resides not in a chain of intermediaries but exclusively and permanently in Christ. Other scholars argue that Paul simply uses "fullness" in its ordinary Greek sense ("the totality, the completeness") without direct reference to a proto-Gnostic system. In either case, the theological point is the same: nothing of God is absent from Christ, and therefore no supplementary mediators are needed.
The phrase "to reconcile all things to himself" (v. 20) raises the question of universal salvation. Christian universalists (such as some in the tradition of George MacDonald or more recently Robin Parry) have argued that if God's goal is to reconcile "all things" -- including things in the heavens -- then ultimately every creature, including fallen angels and unredeemed humanity, will be brought into a reconciled relationship with God. Most Protestant interpreters, however, distinguish between the objective scope of reconciliation (which is cosmic -- Christ's work is sufficient for all and restores the created order) and its subjective application (which requires faith, as Paul immediately makes clear in verses 21-23, where reconciliation is conditional on continuing "in the faith, established and firm"). On this reading, "all things" refers to the restoration of cosmic harmony and the removal of enmity from the created order, not the salvation of every individual. Fallen powers may be "reconciled" in the sense that they are subjected and pacified, not in the sense that they are redeemed. The Reformed tradition has been particularly emphatic that this passage does not teach universalism, pointing to its immediate context as well as to Paul's broader teaching on final judgment (2 Thessalonians 1:9, Romans 2:5-8).
Reconciliation Applied (vv. 21-23)
21 Once you were alienated from God and were hostile in your minds, engaging in evil deeds. 22 But now He has reconciled you by Christ's physical body through death to present you holy, unblemished, and blameless in His presence -- 23 if indeed you continue in your faith, established and firm, not moved from the hope of the gospel you heard, which has been proclaimed to every creature under heaven, and of which I, Paul, have become a servant.
21 And you, who were once alienated and hostile in mind, engaged in evil deeds -- 22 he has now reconciled in the body of his flesh through death, to present you holy, unblemished, and beyond reproach before him, 23 if indeed you continue in the faith, founded and steadfast and not shifting from the hope of the gospel that you heard, which has been proclaimed in all creation under heaven, of which I, Paul, became a servant.
Notes
Paul now moves from the cosmic scope of reconciliation (v. 20) to its personal application to the Colossians. The contrast between "once" and "now" (νυνὶ δέ) is characteristic of Paul's theology (compare Ephesians 2:13, Romans 6:22). The Colossians' former condition is described with three phrases: they were ἀπηλλοτριωμένους ("alienated"), ἐχθρούς ("hostile/enemies"), and engaged in ἔργοις τοῖς πονηροῖς ("evil deeds"). Alienation describes their relational condition; hostility describes their mindset; evil deeds describe their behavior. The hostility was located τῇ διανοίᾳ ("in the mind") -- the problem was not merely behavioral but intellectual and volitional.
The means of reconciliation is emphatically physical: ἐν τῷ σώματι τῆς σαρκὸς αὐτοῦ ("in the body of his flesh"). This seemingly redundant phrase -- "body" and "flesh" together -- is likely directed against an incipient docetism or a spiritualizing tendency in the Colossian heresy that downplayed the reality of Christ's physical incarnation and death. Paul insists that reconciliation was accomplished in a real, physical body through a real, physical death.
The purpose of reconciliation is expressed in three terms: παραστῆσαι ὑμᾶς ἁγίους καὶ ἀμώμους καὶ ἀνεγκλήτους ("to present you holy, unblemished, and beyond reproach"). The three adjectives are drawn from different spheres. ἅγιος ("holy") is cultic language -- set apart for God. ἄμωμος ("unblemished") is sacrificial language -- like an animal without defect offered on the altar. ἀνέγκλητος ("beyond reproach, irreproachable") is legal language -- no charge can be brought against the accused. Together they describe a comprehensive vindication: the believers will stand before God as consecrated, spotless, and legally cleared.
Verse 23 introduces a conditional clause: εἴ γε ἐπιμένετε τῇ πίστει ("if indeed you continue in the faith"). The particle γε ("indeed") strengthens the conditional -- Paul expects that they will continue, but the expectation does not remove the necessity. Perseverance in faith is not optional. Three metaphors describe this perseverance: τεθεμελιωμένοι ("having been founded," a building metaphor), ἑδραῖοι ("steadfast, settled"), and μὴ μετακινούμενοι ("not shifting, not being moved away"). The danger is that the Colossians might be shifted away from the hope of the gospel by the false teachers. Paul's response to false teaching is not merely intellectual refutation but a call to hold firm to what they already have.
Paul's Ministry of the Mystery (vv. 24-29)
24 Now I rejoice in my sufferings for you, and I fill up in my flesh what is lacking in regard to Christ's afflictions for the sake of His body, which is the church. 25 I became its servant by the commission God gave me to fully proclaim to you the word of God, 26 the mystery that was hidden for ages and generations but is now revealed to His saints. 27 To them God has chosen to make known among the Gentiles the glorious riches of this mystery, which is Christ in you, the hope of glory. 28 We proclaim Him, admonishing and teaching everyone with all wisdom, so that we may present everyone perfect in Christ. 29 To this end I also labor, striving with all His energy working powerfully within me.
24 Now I rejoice in my sufferings for you, and I am filling up in my flesh what is lacking of the afflictions of Christ for the sake of his body, which is the church, 25 of which I became a servant according to the stewardship from God that was given to me for you, to fulfill the word of God -- 26 the mystery that has been hidden from the ages and from the generations, but has now been revealed to his saints. 27 To them God chose to make known what are the riches of the glory of this mystery among the Gentiles, which is Christ in you, the hope of glory. 28 Him we proclaim, admonishing every person and teaching every person with all wisdom, so that we may present every person mature in Christ. 29 For this I labor, striving according to his energy that works powerfully within me.
Notes
Verse 24 contains a puzzling statement: ἀνταναπληρῶ τὰ ὑστερήματα τῶν θλίψεων τοῦ Χριστοῦ ἐν τῇ σαρκί μου ("I am filling up what is lacking of the afflictions of Christ in my flesh"). The verb ἀνταναπληρόω ("to fill up in turn, to supply what is lacking") occurs only here in the New Testament. Paul cannot mean that Christ's atoning work on the cross was incomplete -- that would contradict everything he has just said in vv. 15-22. Rather, the "afflictions of Christ" (θλίψεις, not the same word used for Christ's atoning suffering) refer to the ongoing tribulations that the church endures in the present age as the body of Christ. There is a divinely appointed quota of suffering that the church must undergo before Christ returns, and Paul is contributing his share to that total through his own suffering for the Colossians' sake. His imprisonment and hardships are not pointless but serve the church.
Paul describes his ministry as a οἰκονομία given to him by God (v. 25) — the Greek word from which English derives "economy," denoting the management of a household entrusted to a steward. Paul is not freelancing; he is carrying out an assignment. The content of this assignment is πληρῶσαι τὸν λόγον τοῦ Θεοῦ ("to fulfill the word of God") -- not merely to preach it but to bring it to its full expression and completion among the Gentiles.
In verses 26-27, the word of God is defined as τὸ μυστήριον ("the mystery"). In Paul's usage, μυστήριον does not mean something mysterious or incomprehensible but rather a divine secret that was once hidden and has now been revealed. This mystery was ἀποκεκρυμμένον ἀπὸ τῶν αἰώνων καὶ ἀπὸ τῶν γενεῶν ("hidden from the ages and from the generations") -- previous eras and generations did not have access to it. But now it has been ἐφανερώθη ("revealed, made manifest") to his saints.
The content of the mystery is stated simply in verse 27: Χριστὸς ἐν ὑμῖν, ἡ ἐλπὶς τῆς δόξης ("Christ in you, the hope of glory"). The "you" here is plural and refers to the Gentiles -- the surprise of the mystery is that the Messiah of Israel would dwell among and within Gentile believers. The false teachers at Colossae were apparently offering supplementary spiritual experiences and mediators; Paul counters that they already have Christ himself dwelling in them, and he is their hope of future glory. No supplement is needed.
In verse 28, the threefold repetition of πάντα ἄνθρωπον ("every person") is emphatic -- Paul's ministry is universal in scope, not restricted to an elite group of initiates. The false teachers may have offered their deeper knowledge to a select few; Paul admonishes and teaches every person. The goal is to present every person τέλειον ἐν Χριστῷ ("mature/complete in Christ"). The word τέλειος can mean "perfect" or "mature" -- here it carries both senses. Full maturity is found not in esoteric knowledge or mystical experience but in Christ alone.
The chapter closes in verse 29, where Paul names what powers his ministry: κατὰ τὴν ἐνέργειαν αὐτοῦ τὴν ἐνεργουμένην ἐν ἐμοὶ ἐν δυνάμει ("according to his energy that works powerfully within me"). The wordplay on ἐνέργεια ("energy") and ἐνεργέω ("to work, to be active") is difficult to render in English: Christ's energy energizes Paul. His apostolic labor, as exhausting as it is, is ultimately powered not by human willpower but by divine energy at work within him. This is the model for all Christian ministry: human effort empowered by divine power.