CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 1432–1436

1432 The human heart is heavy and hardened. God must give man a new heart. Conversion is first of all a work of the grace of God who makes our hearts return to him: "Restore us to thyself, O LORD, that we may be restored!" God gives us the strength to begin anew. It is in discovering the greatness of God's love that our heart is shaken by the horror and weight of sin and begins to fear offending God by sin and being separated from him. The human heart is converted by looking upon him whom our sins have pierced:

Let us fix our eyes on Christ's blood and understand how precious it is to his Father, for, poured out for our salvation it has brought to the whole world the grace of repentance.

1433 Since Easter, the Holy Spirit has proved "the world wrong about sin," i.e., proved that the world has not believed in him whom the Father has sent. But this same Spirit who brings sin to light is also the Consoler who gives the human heart grace for repentance and conversion.
1434 The interior penance of the Christian can be expressed in many and various ways. Scripture and the Fathers insist above all on three forms, fasting, prayer, and almsgiving, which express conversion in relation to oneself, to God, and to others. Alongside the radical purification brought about by Baptism or martyrdom they cite as means of obtaining forgiveness of sins: effort at reconciliation with one's neighbor, tears of repentance, concern for the salvation of one's neighbor, the intercession of the saints, and the practice of charity "which covers a multitude of sins."
1435 Conversion is accomplished in daily life by gestures of reconciliation, concern for the poor, the exercise and defense of justice and right, by the admission of faults to one's brethren, fraternal correction, revision of life, examination of conscience, spiritual direction, acceptance of suffering, endurance of persecution for the sake of righteousness. Taking up one's cross each day and following Jesus is the surest way of penance.
1436 Eucharist and Penance. Daily conversion and penance find their source and nourishment in the Eucharist, for in it is made present the sacrifice of Christ which has reconciled us with God. Through the Eucharist those who live from the life of Christ are fed and strengthened. "It is a remedy to free us from our daily faults and to preserve us from mortal sins."