Catechism of the Catholic Church

1226 From the very day of Pentecost the Church has celebrated and administered holy Baptism. Indeed St. Peter declares to the crowd astounded by his preaching: "Repent, and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins; and you shall receive the gift of the Holy Spirit." ²⁶ The apostles and their collaborators offer Baptism to anyone who believed in Jesus: Jews, the God-fearing, pagans. ²⁷ Always, Baptism is seen as connected with faith: "Believe in the Lord Jesus, and you will be saved, you and your household," St. Paul declared to his jailer in Philippi. And the narrative continues, the jailer "was baptized at once, with all his family." ²⁸

1227 According to the Apostle Paul, the believer enters through Baptism into communion with Christ's death, is buried with him, and rises with him:

Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, so that as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life. ²⁹

The baptized have "put on Christ." ³⁰ Through the Holy Spirit, Baptism is a bath that purifies, justifies, and sanctifies. ³¹

1228 Hence Baptism is a bath of water in which the "imperishable seed" of the Word of God produces its life-giving effect. ³² St. Augustine says of Baptism: "The word is brought to the material element, and it becomes a sacrament." ³³