I am now rejoicing in my sufferings for your sake, and in my flesh I am completing what is lacking in Christ's afflictions for the sake of his body, that is, the church. (Col 1:24 NRSV)
Commenting on this verse, Methodist New Testament scholar, Morna Hooker, wrote:
Colossians 1:24 provides an interesting example of the way in which commentators have allowed their theological convictions to influence their interpretation of the text. The belief that Christ’s death is decisive and once-for-all has led some of them to shy away from the straight-forward meaning of the words. Another example of this can be seen in the refusal to allow that Paul ever speaks of imitating Christ. Colossians 1:24 reflects the conviction that we have found elsewhere in Paul’s writings, that it is necessary for the Christian to share in the sufferings of Christ and that this participation in suffering can be of benefit to other members of the Christian community. This necessity is not based on the idea that there is a set quota of messianic sufferings that need to be completed. Rather it arises from the representative character of Christ’s death. If Christ died for all, this means not only that all have died, but that they must continue to work out the meaning of dying with Christ. The acceptance of Jesus as Messiah means a willingness to share his experiences. In this sense, at least, the sufferings of Christ are no substitute for ours, but a pattern to which we need to be conformed.
The tendency to stress the belief that Christ’s death was a substitute for ours to the exclusion of the Pauline conviction that Christians must participate in the suffering of Christ is perhaps a very early one. The Corinthians, e.g., seem to have been unable to grasp the idea that there was any place for suffering and humiliation. In their calling: for them, resurrection with Christ was a past event, and this meant that they shared already in his glory, fullness, and riches (cf. 1 Corinthians 4:8). Christ had suffered—and they experienced the resulting glory. He had become for them the substitute for humiliation and death. They failed to see the necessity to share his sufferings. (Morna D. Hooker, “Interchange and Suffering,” in Suffering and Martyrdom in the New Testament, eds. William Horbury and Brian McNeil [Cambridge: Cambridge University Press, 1981], pp.70-83, here, p.82, emphasis added).