Edited from a variety of translations (mentioned in the preface) by H. R. Percival
Cyprian, Liberalis, Caldonius, etc., to their brethren Januarius, etc. Greeting.
When we were together in council, dearest brethren, we read the letter which you addressed to us respecting those who are thought to be baptized by heretics and schismatics, whether, when they come to the one true Catholic Church, they ought to be baptized. Wherein, although ye yourselves also hold the Catholic rule in its truth and fixedness, yet since, out of our mutual affection, ye have thought good to consult us, we deliver not our sentence as though new but, by a kindred harmony, we unite with you in that long since settled by our predecessors, and observed by us; thinking, namely, and holding for certain, that no one can be baptized without the Church, in that there is one Baptism appointed in the holy Church, and it is written, the Lord himself speaking, "They have forsaken me, the Fountain of living water, and hewed them out broken cisterns that can hold no water." Again, holy Scripture admonishes us, and says, "Keep thee from the strange water, and drink not from a fountain of strange water." The water then must first be cleansed and sanctified by the priest, that it may be able, by Baptism therein, to wash away the sins of the baptized, for the Lord says by the prophet Ezekiel, "Then will I sprinkle clean water upon you, and ye shall be cleansed from all your filthiness, and from all your idols will I cleanse you; a new heart also will I give you, and a new spirit will I put within you." But how can he cleanse and sanctify the water, who is himself unclean, and with whom the Spirit is not? whereas the Lord says in Numbers, "And whatsoever the unclean person toucheth shall be unclean." Or how can he that baptizeth give remission of sins to another, who cannot himself free himself from his own sins, out of the Church?
Moreover, the very interrogatory which is put in Baptism, is a witness of the truth. For when we say, "Dost thou believe in eternal life, and remission of sins through the holy Church?" we mean, that remission of sins is not given, except in the Church; but that, with heretics, where the Church is not, sins cannot be remitted. They, therefore, who claim that heretics can baptize, let them either change the interrogatory, or maintain the truth; unless indeed they ascribe a Church also to those who they contend have Baptism.
Anointed also must he of necessity be, who is baptized, that having received the chrism--that is, unction, he may be the anointed of God, and have within him the grace of Christ. Moreover, it is the Eucharist through which the baptized are anointed, the oil sanctified on the altar. But he cannot sanctify the creature of oil, who has neither altar nor church. Whence neither can the spiritual unction be with heretics, since it is acknowledged that the oil cannot be sanctified nor the Eucharist celebrated among them. But we ought to know and remember that it is written, "Let not the oil of a sinner anoint my head;" which the Holy Ghost forewarned in the Psalms, lest any, quitting the track, and wandering out of the path of truth, be anointed by heretics and adversaries of Christ. Moreover, when baptized, what kind of prayer can a profane priest and a sinner offer? in that it is written, "God heareth not a sinner; but if any man be a worshipper of God, and doeth his will, him he heareth."
Reference address : https://www.elpenor.org/ecumenical-councils/carthage-257.asp?pg=4