The Epistle of Paul to the Colossians, (or simply Colossians), is the twelfth book of the New Testament. It was written, according to the text, by Paul the Apostle and Timothy to the Church in Colossae, a small Phrygian city near Laodicea and approximately 100 miles (160 km) from Ephesus in Asia Minor.
Scholars have increasingly questioned Paul's authorship and attributed the letter to an early follower instead. The authenticity of the letter, however, has been defended with equal strength. If Paul was the author, he probably used an amanuensis, or secretary, in writing the letter (Col 4:18), possibly Timothy.
During the first generation after Jesus, Paul's epistles to various churches helped establish early Christian theology. According to Bruce Metzger, it was written in the 50s while Paul was in prison. Colossians is similar to Ephesians, also written at this time. Some critical scholars have ascribed the epistle to an early follower of Paul, writing as Paul. The epistle's description of Christ as pre-eminent over creation marks it, for some scholars, as representing an advanced christology not present during Paul's lifetime. Defenders of Pauline authorship cite the work's similarities to the letter to Philemon, which is broadly accepted as authentic.
The letter may have been written by Paul at Rome during his first imprisonment. Other scholars have suggested that it was written from Caesarea or Ephesus. If the letter is not considered to be an authentic part of the Pauline corpus, then it might be dated during the late 1st century, possibly as late as AD 90.
The letter's authors claim to be Paul and Timothy, but authorship began to be authoritatively questioned during the 19th century. Pauline authorship was held to by many of the early church's prominent theologians, such as Irenaeus, Clement of Alexandria, Tertullian, Origen of Alexandria and Eusebius.
However, as with several epistles attributed to Paul, critical scholarship disputes this claim. One ground is that the epistle's language doesn't seem to match Paul's, with 48 words appearing in Colossians that are found nowhere else in his writings and 33 of which occur nowhere else in the New Testament. A second ground is that the epistle features a strong use of liturgical-hymnic style which appears nowhere else in Paul's work to the same extent. A third is that the epistle's themes related to Christ, eschatology and the church seem to have no parallel in Paul's undisputed works.
Advocates of Pauline authorship defend the differences that there are between elements in this letter and those commonly considered the genuine work of Paul (e.g. 1 Thessalonians). It is argued that these differences can come by human variability, such as by growth in theological knowledge over time, different occasion for writing, as well as use of different secretaries (or amanuenses) in composition. As it is usually pointed out by the same authors who note the differences in language and style, the number of words foreign to the New Testament and Paul is no greater in Colossians than in the undisputed Pauline letters (Galatians, of similar length, has 35 hapax legomena). In regard to the style, as Norman Perrin, who argues for pseudonymity, notes, "The letter does employ a great deal of traditional material and it can be argued that this accounts for the non-Pauline language and style. If this is the case, the non-Pauline language and style are not indications of pseudonymity." Not only that, but it has been noted that Colossians has indisputably Pauline stylistic characteristics, found nowhere else in the New Testament. Advocates of Pauline authorship also argue that the differences between Colossians and the rest of the New Testament are not as great as they are purported to be.
Colossae is in the same region as the seven churches of the Book of Revelation. In Colossians there is mention of local brethren in Colossae, Laodicea, and Hierapolis. Colossae was approximately 12 miles (19 km) from Laodicea and 14 miles (23 km) from Hierapolis. Members of the congregation at Colossae may have been incorporating pagan elements into their practice, including worship of elemental spirits. The Epistle to the Colossians declares Christ's supremacy over the entire created universe and exhorts Christians to lead godly lives. The letter consists of two parts: first a doctrinal section, then a second regarding conduct. Those who believe that the impetus of the letter was a growing heresy in the church see both sections of the letter as opposing false teachers who have been spreading error in the congregation. Others see both sections of the letter as primarily encouragement and edification for a developing church.
I. Introduction (1:1-14)
II. The Supremacy of Christ (1:15-23)
III. Paul's Labor for the Church (1:24-2:7)
IV. Freedom from Human Regulations through Life with Christ (2:8-23)
V. Rules for Holy Living (3:1-4:6)
VI. Final Greetings (4:7-18) 
In its doctrinal sections, Colossians emphatically explains that Christ is begotten before all creation (not created) and is supreme over all that has been created. All things were created through him and for him, and the universe is sustained by him. God had chosen for his complete being to dwell in Christ. The "cosmic powers" revered by the false teachers had been "discarded" and "led captive" at Christ's death. Christ is the master of all angelic forces and the head of the church. Christ is the only mediator between God and humanity, the unique agent of cosmic reconciliation. It is the Father in Colossians who is said to have delivered us from the domain of darkness and transferred us to the kingdom of His beloved Son, not the typical way of articulating salvation today. The Son is the agent of reconciliation and salvation not merely of the church, but in some sense redeems the rest of creation as well ("all things, whether things on earth or things in heaven").
The doctrinal part comprises the first two chapters. Its main theme is developed in Colossians chapter 2, with a warning against being drawn away from Him in whom dwelt all the fullness of the deity, and who was the head of all spiritual powers. Christ was the head of the body of which they were members; and if they were truly united to him, what more did they need?
Colossians praises the spiritual growth of the recipients because of their love for all the set-apart ones in Christ. It calls them to grow in wisdom and knowledge that their love might be principled love and not sentimentality. "Christ in you is your hope of glory!".
"Christ in you, the hope of Glory"
One of the great themes of the doctrinal section of Colossians is promise of union with Christ through the indwelling life of God the Holy Spirit. For example, Colossians 1:27, "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." The Apostle Paul wrote to remind them of this promise and guard them against moving their on going trust from Christ to other philosophies and traditions which did not depend on Christ.
The practical part of the Epistle, enforces various duties naturally flowing from the doctrines expounded. They are exhorted to mind things that are above Colossians 3:1-4, to mortify every evil principle of their nature, and to put on the new man. Many special duties of the Christian life are also insisted upon as the fitting evidence of the Christian character. The letter ends with customary prayer, instruction, and greetings.
Colossians is often categorized as one of the "prison epistles" that include Ephesians, Colossians, Philippians, and Philemon. Colossians has some close parallels with the letter to Philemon: names of some of the same people (e.g., Timothy, Aristarchus, Archippus, Mark, Epaphras, Luke, Onesimus, and Demas) appear in both epistles, and both were written by Paul.
Online translations of the Epistle to the Colossians: