Let me quote the full verse: “I now rejoice in my sufferings for you, and fill up in my flesh what is lacking in the afflictions of Christ.” It is a difficult text for which many different interpretations have been provided, including the claim that the atoning death of Christ needs to be supplemented by the sufferings of believers.
Nonatoning Sufferings
We should immediately exclude the suggestion that the death of Christ is not sufficient to redeem us; that it needs to be supplemented through the sufferings of Paul. Throughout the New Testament it is clearly stated that by virtue of Christ’s suffering and death the problem of sin was resolved once and for all. In fact, in Colossians 1:20-22 it is categorically stated that the blood of Christ has brought reconciliation to us; we are already complete in Him (Col. 2:10). Nothing is lacking! His expiatory death is all that’s needed to be accepted by God (Rom. 3:24, 25), for Christ “put away sin by the sacrifice of Himself” (Heb. 9:26). In our passage Paul is not discussing the atoning sufferings of Christ.
Context
Colossians 1:24-29 forms a thought unit that could help us understand the meaning of verse 24. First, the main topic is the mission of the church, represented by the ministerial call of Paul to preach, teach, and warn every person about the gospel of salvation through Christ (verses 25-28; cf. Eph. 3:1-7). Second, in serving God, Paul experiences “sufferings” (Col. 1:24; Greek pathema, “suffering, misfortune”) for the benefit of Jewish and Gentile believers that constitute the church (verses 24, 27; cf. Acts 9:16). He suffers for them in his own person (“in the flesh”) in the sense that as a result of bringing the gospel and ministering to them he was persecuted and afflicted, but the end result was their salvation through Christ (cf. Col. 1:5, 6; Eph. 3:13). Therefore, he can rejoice in his suffering. Paul knows that, like him, believers also suffer in their service to Christ (2 Cor. 1:6, 7)—they all suffer for Christ (cf. Acts 14:22; Rom. 8:17; 1 Thess. 3:3; 2 Tim. 3:12).
The Suffering of Believers and Christ
It is in that context that Paul offers an understanding of Christian suffering that goes quite deep. We should take the text seriously when it states that in suffering for believers “I [Paul] . . . fill up [Greek antanapleroo, “to complete, finish”] . . . what is lacking [Greek husterema, “need, deficiency, lack] in the afflictions [Greek thlipsis, “affliction, hardship”)] of Christ” (Col. 1:24). Although many explanations have been provided, the text may indicate that Christ’s afflictions did not end after His ascension and that consequently He continues to identify Himself with the church (cf. Acts 9:4). There is something lacking in His work of mediation that is being completed through His interaction with the experiences of the church on earth, more specifically with the afflictions of believers. As they fulfill the mission of the church, Christ is now being afflicted by the afflictions of believers, suggesting that He is somehow experiencing them in Himself. This will come to an end at His return in glory (Rev. 21:3, 4).