Holy baptism holds the first place among all the sacraments, for it is the gate of the spiritual life; through it we become members of Christ and of the body of the church. Since death came into the world through one person, unless we are born again of water and the spirit, we cannot, as Truth says, enter the kingdom of heaven. The matter of this sacrament is true and natural water, either hot or cold. The form is: I baptize you in the name of the Father and of the Son and of the holy Spirit. But we do not deny that true baptism is conferred by the following words: May this servant of Christ be baptized in the name of the Father and of the Son and of the holy Spirit; or, This person is baptized by my hands in the name of the Father and of the Son and of the holy Spirit. Since the holy Trinity is the principle cause from which baptism has its power and the minister is the instrumental cause who exteriorly bestows the sacrament, the sacrament is conferred if the action is performed by the minister with the invocation of the holy Trinity. The minister of this sacrament is a priest, who is empowered to baptize in virtue of his office. But in case of necessity not only a priest or a deacon, but even a lay man or a woman, even a pagan and a heretic, can baptize provided he or she uses the form of the church and intends to do what the church does. The effect of this sacrament is the remission of all original and actual guilt, also of all penalty that is owed for that guilt. Hence no satisfaction for past sins is to be imposed on the baptized, but those who die before they incur any guilt go straight to the kingdom of heaven and the vision of God.
Council of Florence, Sess. 8