In this verse Paul says, “Now, I rejoice in my sufferings for your sake, and in my flesh I am filling up what is lacking in Christ’s afflictions for the sake of his body, that is, the church.” Paul begins with the word “Now” as if to say, “Listen very closely.”

He has written in verses 22 and 23 of the depths of sin from which Christians have been redeemed, and that redemption was through the death of Christ; in order to present them holy and blameless before God. Hence, they are to remember, Christ suffered and died for them. That is the foundation of their faith. We must remind ourselves of this day by day, hour by hour.

Paul is writing from a Roman prison, not at all a comfortable place. He has been chosen by the Lord Jesus to take the gospel to the Gentiles, and his obedience to that calling has resulted in many tribulations. What do you do when your obedience to Christ leads to costly consequences? For the Apostle Paul, it meant to rejoice. Why?

One reason was for the sake of the Colossian Christians. They had learned of Christ through the ministry of Epaphras. He had learned the gospel in Ephesus when Paul was there teaching and preaching. Paul had suffered much for preaching the gospel before he reached Ephesus. He suffered also in Ephesus. The sufferings of Paul are well documented in the New Testament. 

Yet his sufferings were not in vain. The Christians he was writing to had benefited from his suffering. The gospel had come to them because he had been willing to count the cost of following Christ. Paul rejoiced to hear of the souls in Colossae rejoicing in Christ. This was the purpose of Christ’s death. The Lord Jesus said as he neared the cross: “What shall I say? Father, save me from this hour? But for this purpose I have come to this hour. Father, glorify your name.”

For Paul, proclaiming the truth of the cross, the glory of God in so great a salvation, and seeing others come into the kingdom of God was worth the cost of his own sufferings. We should not wonder about this if we know Christ. You might have troubles, and they might be very hard; but they in no way compare to the swarm of worse problems for those who don’t know Christ.

They are still ignorant of their hard hearts toward God. They have neither hope nor future. They are under the power of the devil and death. They do not know the author of life, nor so great a love as the love of the Son of God. Paul rejoiced to see people come to life in Christ. He was on his knees, bound by chains on a stone floor in prison, thanking God for his grace to these souls in Colossae.

Paul is also thinking of God’s sovereignty in his sufferings. That is one of the things he means by “filling up what is lacking in Christ’s afflictions.” Submitting to God’s providence is important in the life of the believer. We must learn not to quarrel with God’s government. Let God do as he pleases as he brings us to heaven. It is no matter what the way is like, or how rugged it is, as long as he brings us there. For the believer in the worst of conditions, God is his still.

What Paul does not mean in the phrase “filling up what is lacking in Christ’s afflictions,” is that his sufferings in anyway supplement Christ’s sufferings, for a right standing with God. Christ made full satisfaction for our sins in his atoning death. His sacrificial death is in no way inadequate, nor does it require any supplementation. It is a complete denial of Christ to think otherwise.

Paul, as a servant, is not greater than the Master. Or as he says in his letter to the Philippians, “It has been granted to you, not only to believe in him, but to suffer for his sake.” So “filling up what is lacking” means identifying yourself with Christ, despite the world’s opposition to Christ.  There will be opposition to Christians in the world. The spirit of the age is against them.  The Christian must see this, so that he does not forget Christ’s cross.

Samuel Rutherford said: “You can’t sneak quietly into heaven without a cross. Crosses form us into his image. They cut away the pieces of our corruption. Lord cut, carve, wound; Lord do anything to form your image in us and make us fit for glory. Whatever direction the wind blows, it will blow us to the Lord.”