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."
This sacrament is also called "the washing of regeneration and renewal by the Holy Spirit," for it signifies and actually brings about the birth of water and the Spirit without which no one "can enter the kingdom of God."
"This bath is called enlightenment, because those who receive this [catechetical] instruction are enlightened in their understanding . . . . Having received in Baptism the Word, "the true light that enlightens every man," the person baptized has been "enlightened," he becomes a "son of light," indeed, he becomes "light" himself:
Baptism is God's most beautiful, precious and magnificent gift. . . .We call it gift, grace, anointing, enlightenment, garment of immortality, bath of rebirth and seal. It is called gift because it is conferred on those who bring nothing of their own; grace since it is given even to the guilty because sin is buried in the water; anointing for it is priestly and royal as are those who are anointed; enlightenment because it radiates light; clothing since it veils our shame; bath because it washes; and seal as it is our guard and the sign of God's Lordship.