Peter, in showing that the Church is one and that only those who are in the Church can be saved, said: "In the Ark of Noah certain persons, numbering only eight, were saved by water, which Baptism effects in like manner for you" (1 Peter 3:20). He proves and demonstrates that the solitary Ark of Noah was the figure of the One Church. If, at the time of this Baptism of the world anyone could have been saved without having been in the Ark of Noah, then he who is outside the Church could now be brought to life by Baptism.
CyprianHe [Christ] protects their faith and gives strength to believers in proportion to the trust that each man who receives that strength is willing to place in him.
CyprianSince the baptismal rebirth takes place only with the one Bride of Christ, where could he be born who is not a son of the Church?
CyprianWhereas there can be but one Baptism, they think they can Baptize; they have abandoned the fountain of life, yet promise the life and grace of the waters of salvation. It is not cleansing which men find there, but soiling; their sins are not washed away, but only added to. That being "born again" does not bring forth sons to God but to the Devil. Born of a lie, they cannot inherit the things which Truth has promised; begotten by the faithless, they are deprived of the grace of faith.
Cyprian