CLAIM: Paul writes, “Now I rejoice in what was suffered for you, and I fill up in my flesh what is still lacking in regard to Christ’s afflictions, for the sake of his body, which is the church” (Col. 1:24). Do believers need to finish the work of Christ on Earth?
RESPONSE: A number of responses are in order:
First, the rest of the NT states that Christ’s work was complete. Jesus purchased our salvation “once for all” (Heb. 9:12; 10:10; 1 Pet. 3:18). Jesus said that he had “accomplished the work which [God] have given [Him] to do” (Jn. 17:4). After he had paid for human sin, Jesus himself said, “It is finished” (Jn. 19:30). The author of Hebrews writes, “He, having offered one sacrifice for sins for all time, sat down at the right hand of God… For by one offering He has perfected for all time those who are sanctified” (Heb. 10:12, 14). Even in the same letter, Paul writes, “In Him you have been made complete” (Col. 2:10). We would be mistaken in thinking that Christ needs the Church to pay for human sin.
Second, the term “afflictions” is never used of Jesus’ work on the Cross. N.T. Wright explains, “The word ‘afflictions’ (thlipsis in the Greek) is never, in fact, used of the cross.” Patzia writes, “Besides, the Greek word used here for suffering (thlipsis) is not used in the New Testament with reference to Christ’s atoning death.” Vaughn agrees, “The word ‘afflictions’ (thlipseōn)… is never employed elsewhere in the NT of the sufferings of Christ on the cross; the reference, then, is to the tribulations our Lord endured in the course of his life and ministry.” Therefore, it’s unlikely that Paul has Jesus’ work on the Cross in mind, when he speaks of Christ’s sufferings here.
Third, Paul is thinking of our mystical union with Christ. Under this view, Jesus suffered once and for all for us in purchasing our salvation, but he continues to suffer through us to spread the message of his salvation. When Jesus confronted Saul on the Damascus road, he asked, “Saul, Saul, why are you persecuting Me? …I am Jesus whom you are persecuting” (Acts 9:4, 5). Since believers are part of Christ’s body (1 Cor. 12:13), he identifies our suffering with his own. Elsewhere, Paul writes, “The sufferings of Christ are ours in abundance” (2 Cor. 1:5), and we have “the fellowship of His sufferings” (Phil. 3:10).
Jesus’ work was complete on the Cross, but since he continues to identify with his Church, he continues to suffer with us until he returns.
 Wright, N. T. (1986). Colossians and Philemon: an introduction and commentary (Vol. 12, p. 93). Downers Grove, IL: InterVarsity Press.
 Patzia, A. G. (2011). Ephesians, Colossians, Philemon (p. 40). Grand Rapids, MI: Baker Books.
 Vaughan, C. (1981). Colossians. In F. E. Gaebelein (Ed.), The Expositor’s Bible Commentary: Ephesians through Philemon (Vol. 11, p. 190). Grand Rapids, MI: Zondervan Publishing House.