Wisdom 11,22-12,1; Psalm 145, 1-2.8-9.10-11.13.14; 2 Thessalonians 1, 11-2,2; St. Luke 19, 1-10
Zaccheus is filled with remorse for his sins, so much so that he promises publicly, before Jesus and other witnesses, to perform reparations for his crimes.
What moves Zaccheus to this sincere contrition for his sins and the vow to change his life, even to a willingness to endanger his livelihood? How does he find within himself such superhuman generosity? He has encountered the transforming supernatural power of Divine Love.
Conversion has a social component because it is a rejection of sin and its social consequences.
"Conversion is accomplished in daily life by gestures of reconciliation, concern for the poor, the exercise and defense of justice and right, (Cf. Am 5:24; Isa 1:17) by the admission of one's 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 reightouesness. Taking up one's cross each day and following Jesus is the surest way of penance." (Cf. Lk 9:23) (CCC 1439)
Sorrow for sins, always necessary for receiving the grace of God's forgiveness, should always accompany one's works of reparation for sin.
"The movement of return to God, called conversion and repentance, entails sorrow for and abhorrence of sins committed, and the firm purpose of sinning no more in the future. Conversion touches the past and the future and is nourished by hope in God's mercy. (CCC 1490)
Sorrow for sin is always required when celebrating the sacrament of Confession in order that the penitent may indeed receive the graces of the sacrament. As well, one's sorrow and experience of God's healing love can and should move one to repair damage or replace what is taken away from others by one's sins.
Reparation, as seen in the example of Zaccheus, may under certain circumstances be a duty for the penitent.
"Every offense committed against justice and truth entails the duty of reparation, even if its author has been forgiven. When it is impossible publicly to make reparation for a wrong, it must be made secretly. If someone who has suffered harm cannot be directly compensated, he must be given moral satisfaction in the name of charity. This duty of reparation also concerns offenses against another's reputation. This reparation, moral and sometimes material, must be evaluated in terms of the extent of the damage inflicted. It obliges in conscience. (CCC 2487)
"During his public life Jesus not only forgave sins, but also made plain the effect of this forgiveness: he reintegrated forgiven sinners into the community of the People of God from which sin had alienated or even excluded them. A remarkable sign of this is the fact that Jesus receives sinners at his table, a gesture that expresses in an astonishing way both God's forgiveness and the return to the bosom of the People of God. (Cf. Lk 15; 19:9.)"(CCC 1443)
Zaccheus was converted from an attraction to evil by his attraction to the love of Christ and a desire to share in it.
"God is infinitely good and all his works are good. Yet no one can escape the experience of suffering or the evils in nature which seem to be linked to the limitations proper to creatures: and above all to the question of moral evil. Where does evil come from? 'I sought whence evil comes and there was no solution,' said St. Augustine, (St. Augustine, Confessions 7,711:PL 32,739.) and his own painful quest would only be resolved by his conversion to the living God. For 'the mystery of lawlessness' is clarified only in the light of the 'mystery of our religion.'(2 Thess 2:7; 1 Tim 3:16.) The revelation of divine love in Christ manifested at the same time the extent of evil and the superabundance of grace.(Cf. Rom 5:20.) We must therefore approach the question of the origin of evil by fixing the eyes of our faith on him who alone is its conqueror. (Cf. Lk 11:21-22; Jn 16:11; 1 Jn 3:8.) (CCC 385)