Salvifici doloris ("redemptive suffering") is a February 1984 Apostolic letter by Pope John Paul II. Its theme was suffering in general in the light of the cross and salvific or redemptive suffering in particular. It was issued in connection with the 1983 Holy Jubilee Year of Redemption.
Its foundational Bible text was taken from the words of the Apostle Paul where he said: "In my flesh I complete what is lacking in Christ's afflictions for the sake of his body, that is, the Church". The meditation flows from Pope John Paul II's own experience of bereavement, illness and pain including his recovery from the assassination attempt of 1981.
In the Cross of Christ not only is the Redemption accomplished through suffering, but also human suffering itself has been redeemed,. Christ, - without any fault of his own - took on himself "the total evil of sin". The experience of this evil determined the incomparable extent of Christ's suffering, which became the price of the Redemption. 
In bringing about the Redemption through suffering, Christ has also raised human suffering to the level of the Redemption. Thus each man, in his suffering, can also become a sharer in the redemptive suffering of Christ.
Those who share in Christ's sufferings have before their eyes the Paschal Mystery of the Cross and Resurrection, in which Christ descends, in a first phase, to the ultimate limits of human weakness and impotence: indeed, he dies nailed to the Cross. But if at the same time in this weakness there is accomplished his lifting up, confirmed by the power of the Resurrection, then this means that the weaknesses of all human sufferings are capable of being infused with the same power of God manifested in Christ's Cross. In such a concept, to suffer means to become particularly susceptible, particularly open to the working of the salvific powers of God, offered to humanity in Christ. In him God has confirmed his desire to act especially through suffering, which is man's weakness and emptying of self, and he wishes to make his power known precisely in this weakness and emptying of self. 
- Colossians 1:24
- Dulles SJ, Cardinal Avery, The Splendor of Truth: The Theological Vision of Pope John Paul II, Crossroad Publishing Company, New York, 2003
- Catechism of the Catholic Church on Vatican Website, Paragraph 618
- Salvifici Doloris §18
- Salvifici Doloris §19
- Salvifici Doloris §23