The Sacrament of Baptism: Welcoming you into the Catholic Faith
Jesus said, "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." (Matthew 28:19)
vitae spiritualis ianua
In the Catechism of the Catholic Church we can read that "Holy Baptism is the basis of the whole Christian life, the gateway to life in the Spirit (vitae spiritualis ianua), and the door which gives access to the other sacraments. Through Baptism we are freed from sin and reborn as sons 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 in the word." (CCC 1213)
The Sacrament of Baptism is often called "The door of the Church". Baptism it is the first of the seven sacraments not only in time but in priority. The reception of the other sacraments depends on baptism. It is the first of the three Sacraments of Initiation, the other two being the Sacrament of Confirmation and the Sacrament of Holy Communion. Once baptized, a person becomes a member of the Catholic Church.
In the Catholic Church baptism is usually administered to infants. There are some Christian denominations who strongly disagree with infant baptism, believing that baptism requires a certain amount of understanding on the part of the person being baptized. There is evidence that infant baptism was practiced from the earliest days of the Church.
St. Paul wrote in his letter to the Colossians that baptism had replaced circumcision (Col. 2:11–12). He refers to baptism as “the circumcision of Christ” and “the circumcision made without hands.” Under the Old Law infants were circumcised as an act of initiation into the Jew Faith. In the Old Testament if a man wanted to become a Jew he had to believe in the God of Israel and be circumcised. In the New Testament, if one wants to become a Christian one must believe in God and Jesus and be baptized. In the Old Testament, those born into Jewish households could be circumcised in anticipation of the Jewish faith in which they would be raised. Thus, in the New Testament, those born in Christian households can be baptized in anticipation of the Christian faith in which they will be raised.
Adults who convert to Catholicism receive the sacrament through unless they have already received a Christian baptism. (If there is any doubt about whether an adult has already been baptized, the priest will perform a conditional baptism.) A person can only be baptized once as a Christian. If a person was baptized as a Lutheran, for example, he or she cannot be "rebaptized" when he or she converts to Catholicism.
Adult baptism normally takes place as part of the Rite of Christian Initiation for Adults (RCIA) and is immediately followed by Confirmation and Communion.