Baptismal regeneration and the Early Church Fathers

[Matt_Black]

Similarly with respect to the Real Presence, I’d be grateful for patristic citings of this doctrine and also paedo-baptism

Yours in Christ

Matt

 

[John_Hiner]

Similarly with respect to the Real Presence, I’d be grateful for patristic citings of this doctrine and also paedo-baptism

Yours in Christ

Matt

Laudetur Iesus Christus.

Dear “Matt Black:”

One good source for such citations is the Catechism of the Catholic Church, which has extensive and helpful footnotes. It is available both online, at scborromeo.org/ccc.htm, and as part of the Biblia Clerus, described in the next paragraph.

I might recommend that you download the free tool called Biblia Clerus, which is made available by the Vatican’s Congregation for the Clergy. It is available at clerus.org/bibliaclerus/index_eng.html. It includes the writings of many church fathers and other ecclesial writings.

Also of great help is the website called, “Scriptur[al] Catholic.” Here are the links to the quotations of church fathers regarding baptism: scripturecatholic.com/baptism.html

Here are the entries regarding the real presence: scripturecatholic.com/the_eucharist.html

I hope these are helpful.

Spiritus Sapientiae tecum.

John Hiner

 

[Ignatius33]

Here are some passages from the Church Fathers on the Real Presence:

1. St. Clement of Rome (third successor to St. Peter and martyr; he knew some of the Apostles and/or disciples who had known Jesus, and he possibly knew Peter himself) admonished a contingent of the Corinthian church that had unjustifiably removed certain presbyters (later called priests), observing:

“Our Apostles knew through our Lord Jesus Christ that there would be strife for the office of bishop. For this reason, therefore, having received perfect knowledge, they appointed those who have already been mentioned, and afterwards added the further provision that, if they should die, other approved men should succeed to their ministry. As for these, then, who were appointed by them, or who were afterwards appointed by other illustrious men with the consent of the whole Church, and who have ministered to the flock of Christ without blame, humbly, peaceably and with dignity, and who have for many years received the commendations of all, we consider it unjust that they be removed from the ministry. Our sin will not be small if we eject from the episcopate those who blamelessly and holily offered its sacrificial gifts” (Letter to the Corinthians [ca. 80/96 AD]).

1. St. Ignatius of Antioch (bishop of Antioch and martyr; he almost certainly knew the Apostle John) referred to the Eucharist as the “medicine of immortality” (a pretty clear reference to Jn. 6:54-56) and elsewhere said:

“Take note of those who hold heterodox opinions on the grace of Jesus Christ which has come to us *, and see how contrary their opinions are to the mind of God . . . They abstain from the Eucharist . . . because they do not confess that the Eucharist is the Flesh of our Savior Jesus Christ . . . Let that be considered a valid Eucharist which is celebrated by the bishop, or by whom he appoints. Wherever the bishop appear, let the people be there; just as wherever Jesus Christ is, there is the Catholic Church” (Letter to the Smyrnaeans [ca. 105 AD] [emphasis added]).

Parenthetically, Protestant patristics scholars like J.N.D. Kelly, Paul Bradshaw and Jaroslav Pelikan (who later converted to Orthodoxy) concur that Ignatius believed in the Real Presence. Conversely, I have never heard of any patristics scholar denying that Ignatius believed in the Real Presence.

1. St. Polycarp (bishop of Smyrna and martyr; he learned directly from the Apostle John) endorsed the orthodoxy of Ignatius’ beliefs concerning the Eucharist (and the office of bishop, i.e., the episcopacy):

“The Epistles of Ignatius written by him to us, and all the rest [of his Epistles] which we have by us, we have sent to you, as you requested. They are subjoined to this Epistle, and by them you may be greatly profited” (Epistle to the Philippians [after 105 AD]).

1. St. Justin Martyr (early apologist and martyr):

“[T]he food which has been made into the Eucharist by the Eucharistic prayer set down by Him . . . is both the flesh and the blood of that incarnated Jesus” (First Apology [148-155 AD]).

1. St. Irenaeus (bishop of Lyons and martyr; he learned directly from Polycarp):

“He took from among creation that which is bread, and gave thanks, saying ‘This is My Body.’ The cup likewise, which is among the creation to which we belong, He confessed to be His Blood. He taught the new sacrifice of the new covenant” (Against Heresies [ca. 180 AD]).

1. Tertullian (apologist who later left the Church for the Montanist sect):

“Likewise, in regard to days of fast, many do not think they should be present at the sacrificial prayers, because their fast would be broken if they were to receive the Body of the Lord. Does the Eucharist, then, obviate a work devoted to God, or does it bind it more to God? Will not your fast be more solemn if, in addition, you have stood at God’s altar? The Body of the Lord having been received and reserved, each point is secured: both the participation in the sacrifice and the discharge of duty” (Prayer [200-206 AD]).

“We offer sacrifices for the dead * on their birthday anniversaries *” (The Crown [211 AD]).

1. St. Clement of Alexandria (theologian):

“‘Eat my flesh,’ He says, ‘and drink My Blood’ [Jn. 6:55]. The Lord supplies us with these intimate instruments . . . O incredible mystery!” (The Instructor of Children [before 202 AD]).

1. St. Hippolytus of Rome (bishop and martyr):

“‘And she [Wisdom] has furnished her table [Prov. 9:2] . . . refers to his [Christ’s] honored and undefiled body and blood, which day by day are administered and offered sacrificially at the spiritual divine table, as a memorial of that first and ever-memorable table of the spiritual divine supper *” (Commentary on Proverbs [217 AD]).

1. Origen (theologian and martyr):

“Formerly, in an obscure way, there was manna for food; now, however, in full view, there is the true food, the Flesh of the Word of God, as He Himself says: ‘My Flesh is truly food, and My Blood is truly drink’” [Jn. 6:56] (Homilies on Numbers [248 AD]).

1. St. Cyprian of Carthage (bishop of Carthage and martyr):

“If Christ Jesus, our Lord and God, is Himself the High Priest of God the Father; and if He offered Himself as a sacrifice to the Father; and if He commanded that this be done in commemoration of Himself – then certainly the priest, who imitates that which Christ did, truly functions in place of Christ” (Letter to Cecil [before 258 AD]).

continued…****

 

[Ignatius33]

1. Aphraates the Persian Sage (bishop):

“With His own hands the Lord presented His own Body to be eaten, and before He was crucified He gave His Blood as drink [at the Last Supper]” (Treatises [336-345 AD]).

1. St. Ephraim (deacon and doctor of the Church):

“But if anyone despise [the Eucharist] or reject it with ignominy, it may be taken as a certainty that he treats with ignominy the Son, who called it and actually made it to be His Body” (Homilies [351 AD]).

1. St. Cyril of Jerusalem (bishop of Jerusalem and doctor of the Church) referred to the Mass as “the spiritual Sacrifice, the bloodless worship, over that propitiatory victim” and wrote:

“Do not, therefore, regard the Bread and the Wine as simply that; for they are, according to the Master’s declaration, the Body and Blood of Christ. Even though the senses suggest to you the other, let faith make you firm” (Catechetical Lectures [350 AD]).

1. St. Athanasius (bishop of Alexandria and doctor of the Church):

“So long as the prayers of supplication and entreaties have not been made, there is only bread and wine. But after the great and wonderful prayers have been contemplated, then the bread is become the Body, and the wine the Blood, of our Lord Jesus Christ” (Sermon to the Newly Baptized [before 373 AD]).

1. St. Hilary of Poitiers (bishop of Poitiers and doctor of the Church):

“As to the reality of His Flesh and Blood, there is no room left for doubt, because now, both by the declaration of the Lord Himself and by our own faith, it is truly Flesh and it is truly Blood. And These Elements bring it about, when taken and consumed, that we are in Christ and Christ is in us” (The Trinity [356-359 AD]).

1. St. Basil the Great (bishop of Caesarea and doctor of the Church):

“To communicate each day and to partake of the holy Body and Blood of Christ is good and beneficial; for He says quite plainly: ‘He that eats My Flesh and drinks My Blood has eternal life’” [Jn. 6:55] (Letter to a Patrician Lady Caesaria [ca. 372 AD]).

1. St. Gregory Nazianzen (bishop of Constantinople and doctor of the Church):

“Cease not to pray and plead for me when you draw down the Word by your word, when in an unbloody cutting you cut the Body and Blood of the Lord, using your voice for a sword” (Letter of Gregory to Amphilochius, Bishop of Iconium [ca. 383 AD]).

1. St. Gregory of Nyssa (bishop of Nyssa):

“The bread again is at first common bread; but when the mystery sanctifies it, it is called and actually becomes the Body of Christ” (Sermon on the Day of Lights or On the Baptism of Christ [before 394 AD]).

1. St. Epiphanius of Salamis (bishop of Salamis):

“For It is round of shape, and devoid of feeling. As to Its power, He means to say even of Its grace, ‘This is really Me’ – and none disbelieves His word. For anyone who does not believe the truth in what He says is deprived of grace and of Savior” (The Man Well-Anchored [374 AD]).

1. Theodore of Mopsuestia (bishop of Mopsuestia):

“At first [the offering] is laid upon the altar as mere bread, and wine is mixed with water; but by the coming of the Holy Spirit it is transformed into the Body and Blood, and thus it is changed into the power of a spiritual and immortal nourishment” (Catechetical Homilies [before 428 AD]).

1. St. John Chrysostom (bishop of Constantinople and doctor of the Church):

“When you see the Lord immolated and lying upon the altar, and the priest bent over that sacrifice praying, and all the people empurpled by that precious blood, can you think that you are still among men and on earth? Or are you not lifted up to heaven?” (The Priesthood [ca. 386 AD]).

Since Chrysostom is known as the “Doctor of the Eucharist,” I can’t resist offering a couple more passages:

“When you see [the Body of Christ] lying on the altar, say to yourself, ‘Because of this Body I am no longer earth and ash, no longer a prisoner, but free. Because of this Body I hope for heaven, and I hope to receive the good things that are in heaven, immortal life, the lot of the angels, familiar conversation with Christ. This Body, scourged and crucified, has not been fetched by death . . . This is that Body which was blood-stained, which was pierced by a lance, and from which gushed forth those saving fountains, one of blood * and the other of water *, for all the world’ [see Jn. 19:34; 1 Jn. 5:6-8]” (Homilies on the First Epistle to the Corinthians [ca. 392 AD]).

“Christ is present. The One who prepared that [Holy Thursday] table is the very One who now prepares this [altar] table. For it is not a man who makes the sacrificial gifts become the Body and Blood of Christ, but He that was crucified for us, Christ Himself. The priest stands there carrying out the action, but the power and the grace is of God. ‘This is My Body,’ [Matt. 26:26] he says. This statement transforms the gifts” (Homilies on the Treachery of Judas [before 407 AD]).

1. St. Ambrose of Milan (bishop of Milan and doctor of the Church):

“We saw the Prince of Priests coming to us, we saw and heard Him offering His blood for us. We follow, inasmuch as we are able, being priests; and we offer the sacrifice on behalf of the people. And even if we are but little merit, still, in the sacrifice, we are honorable. For even if Christ is not now seen as the one who offers the sacrifice, nevertheless it is He Himself that is offered in sacrifices here on earth when the Body of Christ is offered. Indeed, to offer Himself He is made visible in us, He whose word makes holy the sacrifice that is offered” (Commentaries on Twelve of David’s Psalms [381-397 AD]).

continued…**

 

[Ignatius33]

1. St. Jerome (priest and translator of the Latin Vulgate):

“After the type had been fulfilled by the Passover celebration and He had eaten the flesh of the lamb with His Apostles, He takes bread which strengthens the heart of man, and goes on to the true Sacrament of the Passover, so that just as Melchisedech, the priest of the Most High God, in prefiguring Him, made bread and wine an offering, He too makes Himself manifest in the reality of His own Body and Blood” (Commentaries on the Gospel of Matthew [398 AD]).

1. St. Innocent I (pope):

“For unless they shall have eaten the Flesh of the Son of Man and shall have drunk His Blood, they shall not have life in them” (Letter to the Fathers of the Council of Milevis [417 AD]).

1. St. Augustine (bishop of Hippo and doctor of the Church):

“Was not Christ immolated only once in His very Person? In the Sacrament, nevertheless, He is immolated for the people not only on every Easter Solemnity but on every day; and a man would not be lying if, when asked, he were to reply that Christ is being immolated” (Letter to Boniface, a Bishop [408-412 AD]). Since some non-Catholics assert that Augustine denied transubstantiation and the Sacrifice of the Mass based on vaguer language employed in some of his writings, I will offer a few more relevant quotations:

“What you see is the bread and the chalice; that is what your own eyes report to you. But what your faith obliges you to accept is that the bread is the Body of Christ and the chalice the Blood of Christ” (Sermons [391-430 AD]).

“For Christ was carried in His own hands, when, referring to His own Body, He said: ‘This is My Body’ [Matt. 26:26; Mk. 14:22; Lk. 22:19]. For He carried that Body in His hands” (Explanations of the Psalms [inter 392 – 418 AD]).

“What is the sign of Christ, as everyone knows, if not the cross of Christ? For unless that sign be applied, whether to the foreheads of believers, whether to the very water out of which they are regenerated, whether by the oil by which they are anointed with chrism, or whether to the Sacrifice by which they are nourished, none of these is properly administered” (Homilies on the Gospel of John [416-417 AD]).

“The time which interposes between the death of a man and the final resurrection holds souls in hidden retreats, accordingly as each is deserving of rest or of hardship, in view of what it merited when it was living in the flesh. Nor can it be denied that the souls of the dead find relief through the piety of their friends and relative who are still alive, when the Sacrifice of the Mediator is offered for them, or when alms are given in the church. But these things are of profit to those who, when they were alive, merited that they might afterwards be able to be helped by these things. For there is a certain manner of living, neither so good that there is no need of these helps after death, nor yet so wicked that these helps are of no avail after death. There is, indeed, a manner of living so good that these helps are not needed, and again a manner so evil that these helps are of no avail, once a man has passed from this life” (The Enchiridion of Faith, Hope and Love [421 AD]).

“Open your eyes at last, then, any time, and see, from the rising of the sun to its setting, the Sacrifice of Christians is offered, not in one place only, as was established with you Jews, but everywhere; and not to just any god at all, but to Him who foretold it, the God of Israel . . . Not in one place, as was prescribed for you in the earthly Jerusalem, but in every place, even in Jerusalem herself. Not according to the order of Aaron, but according to the order of Melchisedech” (Sermon to the Jews [after 425 AD]).

1. Macarius the Magnesian (bishop of Magnesia):

“[Christ] took the bread and the cup, each in similar fashion, and said: ‘This is My Body and this My Blood’ [Matt. 26:26, 28]. Not a figure of His body nor a figure of His blood, as some persons of petrified mind are wont to rhapsodize, but in truth the Body and Blood of Christ” (Answer-Book or Rather the Only-Begotten Christ Himself to the Pagans [ca. 400 AD]).

1. St. Cyril of Alexandria (bishop of Alexandria and doctor of the Church):

“He states demonstratively: ‘This is My Body,’ and ‘This is My Blood’ [Matt. 26:26-28], lest you might suppose the things that are seen are a figure. Rather, by some secret of the all-powerful God the things seen are transformed into the Body and Blood of Christ, truly offered in sacrifice in which we, as participants, receive the life-giving and sanctifying power of Christ” (Commentary on Matthew [after 428 AD]).

1. Theodoret of Cyr (theologian):

“Beggar: And after the consecration how do you address [the bread and wine]?
“True Believer: Body of Christ and Blood of Christ.
“Beggar: And do you believe you receive the Body of Christ and His Blood?
“True Believer: That is what I do believe” (A Dialogue Between a Beggar and a True Believer [ca. 447-451 AD]).

1. St. Leo the Great (pope and doctor of the Church):

“When the Lord says: ‘Unless you shall have eaten the flesh of the Son of Man and shall have drunk His blood, you shall not have life in you’ [Jn. 6:54], you ought to so communicate at the Sacred Table that you have no doubt whatever of the truth of the Body and Blood of Christ” (Sermons [before 461 AD]).

1. St. Caesar of Arles (bishop of Arles):

“As often as some infirmity overtakes a man, let him who is ill receive the Body and Blood of Christ” (Sermons [before 542 AD]).

continued…

 

[Ignatius33]

1. St. Fulgence of Ruspe (bishop of Ruspe):

“[T]he Holy Catholic Church does not cease in faith and love to offer throughout all the lands of the world a sacrifice of Bread and Wine . . . In those former sacrifices what would be given us in the future was signified figuratively; but in this sacrifice which has now been given us, it is shown plainly” (The Rule of Faith [523-526 AD]).

1. St. Gregory the Great (pope and doctor of the Church):

“The Victim alone saves the soul from eternal ruin, the sacrificing of which presents to us in a mystical way the death of the Only-begotten, who – though He is now risen from the dead and dies no more, and death will no longer have dominion over Him, for He lives immortally and incorruptibly in Himself – is immolated for us again in this mystery of the sacred oblation. For His body is eaten there, His flesh is distributed among the people unto salvation, His blood is poured out, no longer in the hands of the faithless but in the mouth of the faithful. Let us take thought, therefore, of what this sacrifice means for us, which is in constant representation of the suffering of the Only-begotten Son, for the sake of our forgiveness” (Dialogues [593-594 AD]).

1. St. John Damascene (priest and doctor of the Church):

“[T]he bread itself and the wine are made over into the Body and Blood of God. If you inquire into the way in which this happens, let it suffice for you to hear that it is through the Holy Spirit” (The Source of Knowledge [743 AD]).

**) St. Thomas Aquinas (priest and doctor of the Church):

“Some men accordingly, not paying heed to these things, have contended that Christ’s body and blood are not in this sacrament except as a sign, a thing to be rejected as heretical, since it is contrary to Christ’s words. Hence Berengarius, who had been the first deviser of this heresy [he died in 1088 AD], was afterwards forced to withdraw his error, and to acknowledge the truth of the faith” (Summa Theologica III, Q.75, Art. 1 [1265-1274 AD]).

“And this is done by Divine power in this sacrament; for the whole substance of the bread is changed into the whole substance of Christ’s body, and the whole substance of the wine into the whole substance of Christ’s blood. Hence this is not a formal, but a substantial conversion; nor is it a kind of natural movement: but, with a name of its own, it can be called transubstantiation” (id. III, Q.75, Art. 4).

“It is absolutely necessary to confess according to Catholic faith that the entire Christ is in this sacrament” (id. III, Q. 76, Art. 1). Notably, almost one-fifth of Aquinas’ Summa Theologica is devoted to the seven sacraments.

Hope that is helpful. It was passages like these that led me from Evangelical Protestantism to the Catholic Church.

 

[Ignatius33]

Here are some patristic passages dealing with the interpretation of John 3:5, i.e., baptismal regeneration:

St. Justin Martyr:

“Whoever is convinced and believes that what they are taught and told by us is the truth, and professes to be able to live accordingly, is instructed to pray and to beseech God in fasting for the remission of their former sins, while we pray and fast with them. Then they are led by us to a place where there is water; and there they are reborn in the same kind of rebirth in which we ourselves were reborn: in the name of God, the Lord and Father of all, and of our Savior, Jesus Christ, and of the Holy Spirit, they receive the washing with water. For Christ said, ‘Unless you be reborn, you shall not enter into the kingdom of heaven’ [Jn. 3:3] . . . The reason for doing this, we have learned from the Apostles. Since we had no awareness of our first birth, but were compelled to be born of the moist seed through the mutual union of our parents, and were raised in bad habits and in evil training, and so that we might not remain as children of necessity and ignorance, but rather of deliberate choice and knowledge, and in order to obtain in the water the remission of past sins, there is invoked over him who wishes to be reborn and who has repented of his sins, the name of God, the Father and Master of all . . . This washing is called illumination, because it enlightens the intelligence of those who learn these things. Furthermore, the one being illuminated is washed also in the name of Jesus Christ, who was crucified under Pontius Pilate, and in the name of the Holy Spirit, who predicted through the prophets everything concerning Jesus” (First Apology [148-155 AD]).

St. Irenaeus:

“‘And [Naaman] dipped himself . . . seven times in the Jordan’ [2 Kgs. 5:14]. It was not for nothing that Naaman of old, when suffering from leprosy, was purified upon his being baptized, but [this served] as an indication for us. For as we are lepers in sin, we are made clean, by means of the sacred water and the invocation of the Lord, from our old transgressions, being spiritually regenerated as newborn babes, even as the Lord has declared: ‘Except a man be born again through water and the Spirit, he shall not enter into the kingdom of heaven’” [Jn. 3:5] (Fragment 34 [190 AD]).

St. Theophilus of Antioch:

“Moreover, those things which were created from the waters were blessed by God, so that this might also be a sign that men would at a future time receive repentance and remission of sins through water and the bath of regeneration [Titus 3:5] – all who proceed to the truth are born again and receive a blessing from God” (To Autolycus [ca. 181 AD]).

Tertullian:

“[N]o one can attain salvation without baptism, especially in view of the declaration of the Lord, who says, ‘Unless a man shall be born of water, he shall not have life’” [Jn. 3:5] (Baptism [203 AD]).

St. Hippolytus of Rome:

“[Following baptism] the bishop, imposing his hand on them [during the sacrament of confirmation], shall make an invocation, saying: ‘O Lord God, who made them worthy of the remission of sins through the Holy Spirit’s washing unto rebirth, send into them your grace so that they may serve you according to your will: for there is glory to you, to the Father and the Son with the Holy Spirit, in the holy Church, both now and through the ages of ages. Amen’” (The Apostolic Tradition [ca. 215 AD]).

Origen:

“Formerly there was Baptism, in an obscure way, in the cloud and in the sea; now however, in full view, there is regeneration in water and in the Holy Spirit” (Homilies on Numbers [post 244 AD]).

St. Cyprian of Carthage:

“[When] they receive also the baptism of the Church . . . then finally can they be fully sanctified and be the sons of God . . . since it is written, ‘Except a man be born again of water and of the Spirit, he cannot enter into the kingdom of God’” [Jn. 3:5] (Letters 71[72]:1 [253 AD]).

Aphraates the Persian Sage:

“For from Baptism we receive the Spirit of Christ. At that same moment in which the priests invoke the Spirit, heaven opens, and He descends and rests upon the waters; and those who are baptized are clothed in Him. For the Spirit is absent from all those who are born of the flesh, until they come to the water of rebirth; and then they receive the Holy Spirit” (Treatises [inter 336-345 AD]).

St. Cyril of Jerusalem:

“Since man is of a twofold nature, composed of body and soul, the purification also is twofold: the corporeal for the corporeal and the incorporeal for the incorporeal. The water cleanses the body, and the Spirit seals the soul. Thus, having our heart sprinkled by the Spirit and our body washed with pure water [Heb 10:22], we may draw near to God. When you go down into the water, then, regard not simply the water, but look for salvation through the power of the Holy Spirit. For without both you cannot attain to perfection. It is not I who say this, but the Lord Jesus Christ, who has the power in this matter. And He says, ‘Unless a man be born again’ – and He adds the words ‘of water and of the Spirit – he cannot enter into the kingdom of God’” [Jn. 3:5] (Catechetical Lectures [ca. 350 AD]).

St. Athanasius:

“[A]s we are all from earth and die in Adam, so being regenerated from above of water and Spirit, in the Christ are we quickened” (Four Discourses Against the Arians [360 AD]).

continued…

 

[Ignatius33]

St. Basil:

“This then is what it means to be born again of water and Spirit [Jn. 3:5]: just as our dying is effected in the water, our living is wrought through the Spirit. In three immersions and in an equal number of invocations the great mystery of baptism is completed in such a way that the type of death may be shown figuratively, and that by the handing on of divine knowledge the souls of the baptized may be illuminated. If, therefore, there is any grace in the water, it is not from the nature of water but from the Spirit’s presence there” (The Holy Spirit [375 AD]).

St. Gregory of Nyssa:

“[In] the birth by water and the Spirit, [Jesus] himself led the way in this birth, drawing down upon the water, by his own baptism, the Holy Spirit; so that in all things he became the firstborn of those who are spiritually born again, and gave the name of brethren to those who partook in a birth like to his own by water and the Spirit” (Against Eunomius [382 AD]).

St. Gregory Nazianzen:

“Such is the grace and power of baptism; not an overwhelming of the world as of old, but a purification of the sins of each individual, and a complete cleansing from all the bruises and stains of sin. And since we are double-made, I mean of body and soul, and the one part is visible, the other invisible, so the cleansing also is twofold, by water and the Spirit; the one received visibly in the body, the other concurring with it invisibly and apart from the body; the one typical, the other real and cleansing the depths” (Oration on Holy Baptism [388 AD]).

St. Ambrose of Milan:

“The Church was redeemed at the price of Christ’s blood. Jew or Greek, it makes no difference; but if he has believed, he must circumcise himself from his sins [in baptism (Col. 2:11-12)] so that he can be saved . . . for no one ascends into the kingdom of heaven except through the sacrament of baptism . . . ‘Unless a man be born again of water and the Holy Spirit, he cannot enter the kingdom of God’” [Jn. 3:5] (Abraham [387 AD]).

St. John Chrysostom:

“[N]o one can enter into the kingdom of heaven except he be regenerated through water and the Spirit [Jn. 3:5] . . . These [priests] truly are they who are entrusted with the pangs of the spiritual travail and the birth which comes through baptism: by their means we put on Christ, and are buried with the Son of God, and become members of that blessed head [the Mystical Body of Christ]” (The Priesthood [387 AD]).

St. Augustine:

“It is this one Spirit who makes it possible for an infant to be regenerated . . . when that infant is brought to baptism; and it is through this one Spirit that the infant so presented is reborn. For it is not written, ‘Unless a man be born again by the will of his parents’ or ‘by the faith of those presenting him or ministering to him,’ but, ‘Unless a man be born again of water and the Holy Spirit’ [Jn. 3:5]. The water, therefore, manifesting exteriorly the sacrament of grace, and the Spirit effecting interiorly the benefit of grace, both regenerate in one Christ that man who was generated in Adam” (Letters 98:2 [412 AD]). I’ve never seen an early Christian writer interpret the water in John 3:5 to mean amniotic fluid (or something other than the water of Baptism for that matter).

St. Thomas Aquinas (I know he is later than the patristic age, but I always like to include him):

“Our Lord said (Jn. 3:5): ‘Unless a man be born again of water and the Holy Ghost, he cannot enter the kingdom of God’ . . . By Divine institution water is the proper matter of Baptism; and with reason. First, by reason of the very nature of Baptism, which is regeneration unto spiritual life” (Summa Theologica III, Q.66, Art. 3 [1265-1274 AD]).

“Hence it is clear that by Baptism man dies unto the oldness of sin, and begins to live unto the newness of grace. But every sin belongs to the primitive oldness. Consequently every sin is taken away by Baptism” (id. III, Q.69, Art. 1).