2 Continue steadfastly in prayer, being watchful in it with thanksgiving. 3 At the same time, pray also for us, that God may open to us a door for the word, to declare the mystery of Christ, on account of which I am in prison— 4 that I may make it clear, which is how I ought to speak.
5 Walk in wisdom toward outsiders, making the best use of the time. 6 Let your speech always be gracious, seasoned with salt, so that you may know how you ought to answer each person.
As Paul brings to a close his letter to the Colossian church, the center of his message remains the gospel. He uses the phrase in verse 3 of chapter 4, “the mystery of Christ,” asking that he may be granted an open door to declare it. But this is about more than his sharing the gospel, though it is certainly that. In verse two he also enjoins the Colossians to steadfastness in prayer, and thanksgiving. Prayers of thanksgiving for the revelation of the mystery of Christ were how Paul began Colossians 1. So, before he signs off, Paul brings the readers full circle to the beginning of his letter and his emphasis on the gospel, on the pre-eminence of Christ and our reconciliation with God through his death and resurrection.
So Paul’s emphasis remains Christ and his accomplished work of our redemption. As he gives his final instructions to the Colossians, then, they are not instructions that they must carry out in their own strength, but in the power the Christ provides.