After Peter’s address to the people on the day of the Pentecost, those who heard him “were cut to the heart, and said to Peter and to the others Apostles, ‘Brothers, what should we do? ‘Peter said to them, ‘Repent, and be baptized every one of you in the name of Jesus Christ so that your sins may be forgive, and you will receive the gift of the Holy Spirit” (Acts 2:37-38).

Baptism in the name of Jesus is the sign of the faith in Jesus and the acceptance of his teaching, according to his command to his disciples before his Ascension to heaven: “All authority in heaven and on earth has been given to me. Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything that I have commanded you, and remember, I am with you always to the end of the age” (Mt 28:18-20).

“Holy Baptism is the basis of the whole Christian life, the gateway to life in the Spirit, and the door which gives access to the other sacraments. Through Baptism we are freed from sin and reborn as children of God, we become members of Christ, are incorporated into the Church and made sharers in her mission. Baptism is the sacrament of regeneration, through water and in the word. This sacrament is called Baptism, after the central rite by which it is carried out: to baptize (Creek baptizein) means to plunge or immerse, the plunge into the water symbolizes the catechumen’s burial into Christ’s death, from which he rises up by resurrection with him, ‘as a new creature’ (2 Corinthians 5: 17, Galatians 6: 15)” Catechism of the Catholic Church, Par 1213.

1. A New Creature

In his encounter with Nicodemus, Jesus speaks of the necessity in order to enter the Kingdom of God, to “be born anew” or according to another translation, “to be born from above.” “Very truly, I tell you, no one can see the Kingdom of God without being born from above… No one can enter the Kingdom of God without being born of water and Spirit. What is born from the flesh is flesh and what is born from the Spirit is spirit.” (John3: 3-5)

This new birth divinizes man, by renewing him by the Spirit of God: he is “born of God” and “God’s seed abides in him” (1 John 3:9). This is what also St. Peter means by saying we became “participants of the divine nature” (2 Peter 1:4). The Father of the Church compare the effect of the Holy Spirit in the soul of the baptized to the effect of a piece of iron which, when put in fire, becomes burning like the fire: the iron participates in fire’s nature.

St. Paul speaks of this new life as participation in the death and Resurrection of Jesus, death to sin and resurrection to a new life: “therefore we have been buried with him by baptism into death, so that, just as Christ was raised from the dead by the glory of the Father, so we too might walk in newness of life” (Romans 6:4_5)

2.  Baptism and the Original Sin

The original sin is a state of sin, which every new born in the flesh inherits since the first man called by the Book of Genesis “Adam”. Christianity, based on what Jesus said, and on what the Apostles believed and proclaimed in the New Testament, believes that, by Baptism, one passes from the state of sin to the state of grace, from the state of “the old Adam” to the stat of “the new Adam”, who is Jesus Christ himself, who ushered in a new being and a new way of living. This is the meaning of the expressions like “to become a new creature”, to be born “anew”, to be born “from above”, to be born from the “water and the Spirit”, to become “participants of the divine nature”. All these expressions mean that Baptism starts in the life of the baptized a new life, a new existence: “If anyone is in Christ, there is a new creation” (2 Corinthians 5: 17)

This new existence in Christ is the real human existence according to God’s will since he created man. This real human existence is what the Book of Genesis describes in a symbolic way in the paradise before Adam’s sin. By Baptism, on puts on Christ, enters a new state of being, and starts a new way, the way which is Christ himself (“I am the way”, says Jesus, “and the Truth and the Life” – John 14:6), a way of grace, of holiness and of union with God. This does not mean that baptized is no more exposed to the various temptations of the sin, he remains a human being, and he has to struggle his whole life to stay faithful to the grace he has received by Baptism. Christian life is a long journey, in which the Christian works every day to become more and more “what he is” as Christian. His goal is to reach “to the maturity, to the measure of the full stature of Christ” (Ephesians 4:13).

We said, when we spoke of the creation of man, that God created man in his image and likeness, and this image is the image of his Son Jesus Christ. Baptism is the restoration in the human being of this image of Christ and the beginning of a new life, in which the Christian aims at becoming “what he is” as a new creature n Jesus Christ.

3. Baptism is Incorporation into the Church, the Body of Christ

The mystery of God’s will, which God made known to us, “according to his good purpose that he set forth I Christ, as a plan for the fullness of time” is “ to gather up all things in him, things in the heaven and things on earth.” (Ephesians 1:9_ 10)

By uniting every baptized to Christ, all those who are baptized constitute the Church, which is the Body of Christ: “Baptism makes us members of the Body of Christ: ‘therefore… we are members one of another’ (Ephesians 4: 25). Baptism incorporate us into the Church. From the baptismal fonts is born the one People of God of the new Covenant, which transcends all the natural of human limits of nation, cultures, races, and sexes: ‘For in the one Spirit we were all baptized into on body’ (1 Corinthians 12:13). Catechism of the Catholic Church, Par. 1267.

“The Baptized have become ‘living stones’ to be ‘built into a spiritual house, to be a holy priesthood’ (1 Peter 2:5). By Baptism they share in the priesthood of Christ, in royal priesthood, a holy nation, God’s own people, that they may declare the wonderful deeds of him who called them out of darkness into his marvelous light’ (1 Peter 2:9). Baptism gives a share in the common priesthood of all believers.

4. One Baptism

Baptism is given only once. If it is valid, it is not to be repeated. A baptism is valid if it is performed in a Church who believes in the Holy Trinity and in a rite where the celebrant uses water, while reciting the formula “in the name of the Father and of the Son and of the Holy Spirit.”

“Incorporated into Christ by Baptism, the person baptized is configured to Christ. Baptism seals the Christian with the indelible mark (character) of his belonging to Christ. No sin can erase this mark, even if sin prevents Baptism from bearing the fruits of salvation. Given once for all, Baptism cannot be repeated.” The reason is that once God have given anyone, by Baptism, the grace of adoption in Jesus Christ, he will never retract his grace. The prodigal son, in the parable given by Jesus in St. Luke, took “his share of the estate” and left his father’s house “for a distant country where he squandered his money on a life of debauchery” (Luke 15:13), “his share of the estate” is a symbol of the grace given to man by God, and the life of debauchery is the life of sin. When he came back repentant, his Father didn’t reject him, but made a feast to celebrate his returning. “If we are faithless”, says St. Paul, “he [Christ] remains faithful, for he cannot deny himself’ (2 Timothy 2:13).