The Catechism on Suffering

If God the Father almighty, the Creator of the ordered and good world, cares for all his creatures, why does evil exist? To this question, as pressing as it is unavoidable and as painful as it is mysterious, no quick answer will suffice. Only Christian faith as a whole constitutes the answer to this question: the goodness of creation, the drama of sin and the patient love of God who comes to meet man by his covenants, the redemptive Incarnation of his Son, his gift of the Spirit, his gathering of the Church, the power of the sacraments and his call to a blessed life to which free creatures are invited to consent in advance, but from which, by a terrible mystery, they can also turn away in advance. There is not a single aspect of the Christian message that is not in part an answer to the question of evil.

Catechism of the Catholic Church, 309

The fact that God permits physical and even moral evil is a mystery that God illuminates by his Son Jesus Christ who died and rose to vanquish evil. Faith gives us the certainty that God would not permit an evil if he did not cause a good to come from that very evil, by ways that we shall fully know only in eternal life.

Catechism of the Catholic Church, 324

Union with the passion of Christ. By the grace of this sacrament the sick person receives the strength and the gift of uniting himself more closely to Christ’s Passion: in a certain way he is consecrated to bear fruit by configuration to the Savior’s redemptive Passion. Suffering, a consequence of original sin, acquires a new meaning; it becomes a participation in the saving work of Jesus.

Catechism of the Catholic Church, 1521

The way of perfection passes by way of the Cross. There is no holiness without renunciation and spiritual battle. Spiritual progress entails the ascesis and mortification that gradually lead to living in the peace and joy of the Beatitudes: He who climbs never stops going from beginning to beginning, through beginnings that have no end. He never stops desiring what he already knows.

Catechism of the Catholic Church, 2015

“In its various forms – material deprivation, unjust oppression, physical and psychological illness and death – human misery is the obvious sign of the inherited condition of frailty and need for salvation in which man finds himself as a consequence of original sin. This misery elicited the compassion of Christ the Savior, who willingly took it upon himself and identified himself with the least of his brethren. Hence, those who are oppressed by poverty are the object of a preferential love on the part of the Church which, since her origin and in spite of the failings of many of her members, has not ceased to work for their relief, defense, and liberation through numerous works of charity which remain indispensable always and everywhere.”

Catechism of the Catholic Church, 2448

Why does Jesus call upon his disciples to take up their cross? By calling his disciples to take up their cross and follow him Jesus desires to associate with his redeeming sacrifice those who are to be its first beneficiaries.

Compendium of the Catechism of the Catholic Church, 123

Are all called to Christian holiness? All the faithful are called to Christian holiness. This is the fullness of Christian life and the perfection of charity and it is brought about by intimate union with Christ and, in him, with the most Holy Trinity. The path to holiness for a Christian goes by way of the cross and will come to its fulfillment in the final resurrection of the just, in which God will be all in all.

Compendium of the Catechism of the Catholic Church, 428