Read Colossians 4 at Bible Gateway.
The greater portion of Col 4 forms its own chiastic structure, with an interesting central axis:
1a) Col 4:3, For which I am in chains;
1b) Col 4:3-4, Pray that I may speak the mystery of Christ, and make it manifest, as I ought;
1c) Col 4:5-6, Walk in wisdom toward those outside;
1d) Col 4:7-9, That he may know your circumstances and comfort your hearts (chiasm);
1e) Col 4:10a, Aristarchus my fellow prisoner greets you;
central axis) Col 4:10b, And Mark (about whom you received instructions; if he comes to you, welcome him);
2e) Col 4:11a, Jesus who is called Justus greets you;
2d) Col 4:11b, These fellow workers have proved to be a comfort to me;
2c) Col 4:12-16, Ephaphrus, who walks in zeal toward those inside (Colossae, Laodicea, Hierapolis);
2b) Col 4:17, Take heed to the ministry which you have received from the Lord, that you may fulfill it;
2a) Col 4:18, Remember my chains.
Col 4:7-9 (1d element above)
1a) Col 4:7, Tychicus, beloved and faithful, will tell you all the news about me;
central axis) Col 4:8, I am sending him that he may know your circumstances and comfort your hearts;
2a) Col 4:9, Onesimus, faithful and beloved, will make known to you all that is happening here.
Now the central axis of Col 4:10 is interesting, because Paul is instructing the church to welcome Mark the cousin of Barnabus, about whom they received instructions. It makes it sound as if the church had to be told to welcome Mark, because at some point the church was not welcoming Mark.
According to the earliest church tradition, this Mark the cousin of Barnabus, is one and the same as he who was later known as Mark the Evangelist, who wrote the Gospel of Mark.
Now why would the church not welcome Mark the cousin of Barnabus? After all, in the very earliest days of the church, the assembly of the believers met in John Mark’s mother’s house (Act 12:12). It appears that Barnabus and Silas went to Antioch from Jerusalem after this, to minister to the church, and John Mark accompanied them (Act 12:25). From Antioch, the Spirit set apart Paul and Barnabus to preach the gospel to the Gentiles, and John Mark accompanied them as their assistant (Act 13:1-5).
But we find later, when Barnabus suggested to Paul that they once again return a second time to all the places where the gospel had been established on their first journey, that they had a sharp contention over John Mark:
Then after some days Paul said to Barnabas, “Let us now go back and visit our brethren in every city where we have preached the word of the Lord, and see how they are doing.” Now Barnabas was determined to take with them John called Mark. But Paul insisted that they should not take with them the one who had departed from them in Pamphylia, and had not gone with them to the work. Then the contention became so sharp that they parted from one another. And so Barnabas took Mark and sailed to Cyprus; but Paul chose Silas and departed, being commended by the brethren to the grace of God. Act 15:36-40
Mark departed from them, and abandoned the work. For whatever reason, he did not stay the course and remain faithful. Barnabus was willing to look with grace on this lapse, wanting to give Mark a second chance, but Paul was unwilling to entrust the work of the gospel to one who had already proven unfaithful. The disagreement was so sharp that Paul and Barnabus went their separate ways.
But here, in the letter to Colossae, Paul, not Barnabus, is instructing the church to welcome Mark should he come to them. Perhaps the instructions about Mark, which the church received, was an account of the reconciliation between Paul and Barnabus and John Mark, and the anointing and ministry which has proven to come forth from Mark, once he was given a second chance.
Do you think you have blown it so bad that God can’t redeem it? No. Do you have burned bridges and broken fellowship behind you? Not too hard for God. Don’t you just love that the God we serve is the God who specializes in reconciliation and second chances?