What is justification, in Catholic teaching?

Justification is the gracious work by which God forgives our sins, frees us from sin’s power, and makes us righteous in Christ. It is both forgiveness and a real interior renewal.

What God does. Through Christ’s saving death and Resurrection, God moves a sinner from the state of sin into the life of grace. Justification includes the remission of sins, sanctification, and the renewal of the inner person (CCC 1987-1991). God does not merely overlook sin or attach an external label to us. He gives sanctifying grace, making us adopted children who share in His divine life (CCC 1996-1999; Rom 5:5).

Where justification begins. The grace of the Holy Spirit awakens faith, conversion, and repentance. Adults respond freely to that grace, but they cannot produce or earn the beginning of justification. God always acts first. No one can merit the initial grace of forgiveness and justification (CCC 1989, 2010). Christ earned this gift for us through His Passion, and it is ordinarily conferred in Baptism (CCC 1992; Rom 6:3-4; Titus 3:5-7).

Faith and Baptism. Faith is necessary because justification brings us into communion with Christ. Jesus commands faith and Baptism, and the apostles preach both (Mk 16:16; Acts 2:38). In infant Baptism, the Church supplies the profession of faith, and the child receives grace without any prior personal achievement. In an adult, grace calls forth faith, repentance, and the desire to receive Baptism. Every part of this response remains dependent on God’s grace.

Growth after justification. Justification begins a new life rather than ending the Christian struggle. The justified person can grow in holiness through prayer, the sacraments, obedience, and works of charity. These actions have value because the Holy Spirit works within the believer (CCC 1993, 2008). Serious sin can destroy sanctifying grace, but Christ restores the repentant through the Sacrament of Reconciliation (CCC 1446, 1861).

What Catholics should do. Trust Christ rather than your own achievements. Receive Baptism if you are unbaptized. If you are already baptized, remain close to Christ through faith, prayer, the Eucharist, charity, and regular confession. Justification is God’s free gift, and that gift is meant to transform your whole life.