In this passage from the Letter to the Colossians, Paul teaches us a remarkable and penetrating theology of suffering. In order to understand Paul's doctrine, we must first of all avoid all misunderstanding concerning the nature of Jesus' suffering. That suffering was sufficient to save all of humankind: there was nothing lacking to Jesus' sufferings.

A memorable phrase by a much later writer succinctly encapsulates Paul's theology: Christ is in agony until the end of time. Historically, Jesus suffered his passion and death in his human body. As the Risen Christ, he no longer suffers in this way, but by his resurrection he is united with us in his mystical body, the Church. Just as Jesus, the Messiah, had to suffer and so enter into his glory, in the same way the Church on earth will suffer and so enter into glory. That suffering is both the corporate suffering of the whole Church and the personal suffering becomes part of the suffering of the mystical body of Christ. Thus, each individual Christian can "make up all that has still to be undergone by Christ for the sake of his body, the Church."