Nicene and Post-Nicene Fathers, Vol. IV:
Writings in Connection with the Donatist Controversy.: Chapter 1

Chapter 1.—1.  It might perhaps have been sufficient, that after the reasons have been so often repeated, and considered, and discussed with such variety of treatment, supplemented too, with the addition of proofs from holy Scripture, and the concurrent testimony of so many passages from Cyprian himself, even those who are slow of heart should thus understand, as I believe they do, that the baptism of Christ cannot be rendered void by any perversity on the part of man, whether in administering or receiving it.  And when we find that in those times, when the point in question was decided in a manner contrary to ancient custom, after discussions carried on without violation of saving charity and unity, it appeared to some even eminent men who were bishops of Christ, among whom the blessed Cyprian was specially conspicuous, that the baptism of Christ could not exist among heretics or schismatics, this simply arose from their not distinguishing the sacrament from the effect or use of the sacrament; and because its effect and use were not found among heretics in freeing them from their sins and setting their hearts right, the sacrament itself was also thought to be wanting among them.  But if we turn our eyes to the multitude of chaff within the Church, since these also who are perverse and lead an abandoned life in unity itself appear to have no power either of giving or retaining remission of sins, seeing that it is not to the wicked but the good sons that it was said, "Whosesoever sins ye remit, they are remitted unto them; and whosesoever sins ye retain, they are retained," 1582 yet that such persons both have, and give, and receive the sacrament of baptism, was sufficiently manifest to the pastors of the Catholic Church dispersed over the whole world, through whom the original custom was afterwards confirmed by the authority of a plenary Council; so that even the sheep which was straying outside, and had received the mark of the Lord from false plunderers outside, if it seek the salvation of Christian unity, is purified from error, is freed from captivity, is healed of its wound, and yet the mark of the Lord is recognized rather than rejected in it; since the mark itself is often impressed both by wolves and on wolves, who seem indeed to be within the fold, but yet are proved by the fruits of their conduct, in which they persevere even to the end, not to belong to that sheep which is one in many; because, according to the foreknowledge of God, as many sheep wander outside, so many wolves lurk treacherously within, among whom the Lord yet knoweth them that are His, which hear only the voice of the Shepherd, even when He calls by the voice of men like the Pharisees, of whom it was said, "Whatsoever they bid you observe that observe and do." 1583

2.  For as the spiritual man, keeping "the end of the commandment," that is, "charity out of a pure heart, and of a good conscience, and of faith unfeigned," 1584 can see some things less clearly out of a body which is yet "corruptible and presseth down the soul," 1585 and is liable to be otherwise minded in some things which God will reveal 1586 to him in His own good time if he abide in the same charity, so in a carnal and perverse man something good and useful may be found, which has its origin not in the man himself, but in some other source.  For as in the fruitful branch there is found something which must be purged that it may bring forth more fruit, so also a grape is often found to hang on a cane that is barren and dry or fettered.  And so, as it is foolish to love the portions which require purgp. 480 ing in the fruitful branch, while he acts wisely who does not reject the sweet fruit wherever it may hang, so, if any one cuts himself off from unity by rebaptizing, simply because it seemed to Cyprian that one ought to baptize again those who came from the heretics, such a man turns aside from what merits praise in that great man, and follows what requires correction, and does not even attain to the very thing he follows after.  For Cyprian, while grievously abhorring, in his zeal for God, all those who severed themselves from unity, thought that thereby they were separated from baptism itself; while these men, thinking it at most a slight offense that they themselves are severed from the unity of Christ, even maintain that His baptism is not in that unity, but issued forth with them.  Therefore they are so far from the fruitfulness of Cyprian, as not even to be equal to the parts in him which needed purging.

Footnotes

John xx. 23.

Matt. xxiii. 3.

1 Tim. i. 5.

Wisd. ix. 15.

Phil. iii. 15.