Today’s Catechism sections discuss the Grace and effects of Baptism. Supporting material comes from the “Summa Theologica”.

VII. The Grace of Baptism

1262 The different effects of Baptism are signified by the perceptible elements of the sacramental rite. Immersion in water symbolizes not only death and purification, but also regeneration and renewal. Thus the two principal effects are purification from sins and new birth in the Holy Spirit.64

For the forgiveness of sins . . .

1263 By Baptism all sins are forgiven, original sin and all personal sins, as well as all punishment for sin.65 In those who have been reborn nothing remains that would impede their entry into the Kingdom of God, neither Adam's sin, nor personal sin, nor the consequences of sin, the gravest of which is separation from God.

1264 Yet certain temporal consequences of sin remain in the baptized, such as suffering, illness, death, and such frailties inherent in life as weaknesses of character, and so on, as well as an inclination to sin that Tradition calls concupiscence, or metaphorically, "the tinder for sin" (fomes peccati); since concupiscence "is left for us to wrestle with, it cannot harm those who do not consent but manfully resist it by the grace of Jesus Christ."66 Indeed, "an athlete is not crowned unless he competes according to the rules."67

"A new creature"

1265 Baptism not only purifies from all sins, but also makes the neophyte "a new creature," an adopted son of God, who has become a "partaker of the divine nature,"68 member of Christ and coheir with him,69 and a temple of the Holy Spirit.70

1266 The Most Holy Trinity gives the baptized sanctifying grace, the grace of justification:
- enabling them to believe in God, to hope in him, and to love him through the theological virtues;
- giving them the power to live and act under the prompting of the Holy Spirit through the gifts of the Holy Spirit;
- allowing them to grow in goodness through the moral virtues.
Thus the whole organism of the Christian's supernatural life has its roots in Baptism.

St. Thomas Aquinas discusses the removal of sins as a result of Baptism in the “Summa Theologica” (3, 69, 1).

Article 1. Whether all sins are taken away by Baptism?

Objection 1. It seems that not all sins are taken away by Baptism. For Baptism is a spiritual regeneration, which corresponds to carnal generation. But by carnal generation man contracts none but original sin. Therefore none but original sin is taken away by Baptism.

Objection 2. Further, Penance is a sufficient cause of the remission of actual sins. But penance is required in adults before Baptism, according to Acts 2:38: "Do penance and be baptized every one of you." Therefore Baptism has nothing to do with the remission of actual sins.

Objection 3. Further, various diseases demand various remedies: because as Jerome says on Mark 9:27-28: "What is a cure for the heel is no cure for the eye." But original sin, which is taken away by Baptism, is generically distinct from actual sin. Therefore not all sins are taken away by Baptism.

On the contrary, It is written (Ezekiel 36:25): "I will pour upon you clean water, and you shall be cleansed from all your filthiness."

I answer that, As the Apostle says (Romans 6:3), "all we, who are baptized in Christ Jesus, are baptized in His death." And further on he concludes (Romans 6:11): "So do you also reckon that you are dead to sin, but alive unto God in Christ Jesus our Lord." Hence it is clear that by Baptism man dies unto the oldness of sin, and begins to live unto the newness of grace. But every sin belongs to the primitive oldness. Consequently every sin is taken away by Baptism.

Reply to Objection 1. As the Apostle says (Romans 5:15-16), the sin of Adam was not so far-reaching as the gift of Christ, which is bestowed in Baptism: "for judgment was by one unto condemnation; but grace is of many offenses, unto justification." Wherefore Augustine says in his book on Infant Baptism (De Pecc. Merit. et Remiss. i), that "in carnal generation, original sin alone is contracted; but when we are born again of the Spirit, not only original sin but also wilful sin is forgiven."

Reply to Objection 2. No sin can be forgiven save by the power of Christ's Passion: hence the Apostle says (Hebrews 9:22) that "without shedding of blood there is no remission." Consequently no movement of the human will suffices for the remission of sin, unless there be faith in Christ's Passion, and the purpose of participating in it, either by receiving Baptism, or by submitting to the keys of the Church. Therefore when an adult approaches Baptism, he does indeed receive the forgiveness of all his sins through his purpose of being baptized, but more perfectly through the actual reception of Baptism.

Reply to Objection 3. This argument is true of special remedies. But Baptism operates by the power of Christ's Passion, which is the universal remedy for all sins; and so by Baptism all sins are loosed.

Footnotes

64 Cf. ⇒ Acts 2:38; ⇒ Jn 3:5[ETML:C/].
65 Cf. Council of Florence (1439): DS 1316.
66 Council of Trent (1546): DS 1515.
67 ⇒ 2 Tim 2:5.
68 ⇒ 2 Cor 5:17; ⇒ 2 Pet 1:4; cf. ⇒ Gal 4:5-7.
69 Cf. ⇒ 1 Cor 6:15; ⇒ 12:27; ⇒ Rom 8:17.
70 Cf. ⇒ 1 Cor 6:19.