Since it is recognized that it is extremely rare to find men entirely devoid of the religious sense, some people entertain the hope that nations [...] in spite of their differing religious viewpoints, may be brought to unite as brothers in the profession of certain doctrines as a common foundation of the spiritual life. [...] Certainly efforts such as these cannot receive the approbation of Catholics, for they rest on that false opinion which holds any opinion whatever to be more-or-less praiseworthy and good. [...] Those who hold this opinion are not only in gross error, they even debase the concept of true religion and, little by little, lapse into Naturalism and Atheism. [...] He who refuses to have the Church for his Mother will not have God for his Father. When St. Augustine speaks of man's last end, he hastens to add this counsel to any one who wishes to reach that end: "Their attempt will be useless if they do not submit to the Catholic Church, and humbly obey her, for she alone has been divinely instituted to give light and strength to souls, without which they will necessarily stray from the right path." Would to God they had listened to the voice of Augustine in the past! And would to God that everyone might hear him today who rends the seamless robe of Christ. and casts himself miserably outside the path of salvation. Pope Pius XI

"She is a garden enclosed, My Sister, My Spouse, a garden enclosed: a fountain sealed up" (Canticles 4:12). These words of Holy Scripture are applied, according to the Fathers, to the Catholic Church, the immaculate spouse of Christ; they distinguish her from infidel or heretical sects, so that men will know whom to follow and whom to avoid in their search for eternal life. Pope Leo XIII

INTERFAITH UNIONS CONDEMNED

To know whom to avoid is a great means of saving our souls. [...] Thus, the Church forbids the faithful to communicate with those unbelievers who have forsaken the faith by corrupting it, such as heretics, or by renouncing it, such as apostates. St. Thomas Aquinas

Thou shalt not sow thy vinyard with different seeds, lest both the seed that thou hast sown and the fruit of the vinyard be sanctified together. Deuteronomy 22:9

And the good seed are the children of the kingdom; and the cockle are the children of the wicked one. St. Matthew 13:38

If you eat the words of God in the Church, and also eat them in the synagogue of the Jews, you transgress the commandment which says: "In one House shall it be eaten" (Exodus 12:46). Origen

Whence it sometimes happens through error that Christians mingle with the women of Jews and Mohammedans and, on the other hand, Jews and Mohammedans mingle with those of Christians. Therefore, in order that such ruinous commingling of this kind through error may not serve as a refuge for further excuse for excess, We decree that such people of both sexes, that is, Jews and Mohammedans, be distinguished in public by a difference in dress in every province of Christendom and at all times, since this was also enjoined on such people by Moses. IV Lateran Council

Is it permitted for Christians to be present at, or to take part in, conventions, gatherings, meetings, or societies of non-Catholics which aim to associate together under a single agreement everyone who, in any way, lays claim to the name of Christian? In the negative! [...] It is clear, therefore, why this Apostolic See has never allowed its subjects to take part in the assemblies of non-Catholics. There is only one way in which the unity of Christians may be fostered, and that is by furthering the return to the one true Church of Christ for those who are separated from her. Pope Pius XI

Those who are members of the Church are not to be permitted to go into the cemeteries of any of the heretics for the purpose of prayer or veneration. If they do, they are to be excommunicated. Council of Laodicea

CHRISTIANS MUST SHUN PROTESTANTS

Wherefore, since outside the Catholic Church there is nothing perfect, nothing undefiled, the Apostle declaring that "all that is not of faith is sin" (Romans 14:23), we are in no way likened with those who are divided from the unity of the Body of Christ; we are joined in no communion. Pope St. Leo the Great

Do not work together with unbelievers, for what does justice have in common with injustice? II Corinthians 6:14

"The Lord will cut off their necks" (Psalm 128:4). Let their destiny be shared by all heretics who hate the Church of Christ. "Let them be like the grass on the housetops, which withers before it is plucked up" (Psalm 128:6). [...] For of all the holy ones who shall pass by, from the Apostles even until now, not one has blessed them in the name of the Lord. And he who has not received a blessing from the blessed Apostle Peter, or from the Apostles and their successors, and in this state has deceived people by his teachings, such a person incurs a curse because he has usurped a blessing - a curse by which he withers away before he is plucked up, that is, before he dies. While he seems to live in the body, he is already withered away in the spirit. From such men we, being separated, guarding most perfectly the Catholic faith, find life everlasting. Arnobius the Younger

There are some, you know, who are accustomed to go around with the Name on their lips while they indulge in certain practices at variance with It and an insult to God. You must shun these men as you would wild beasts: they are rabid dogs that bite in secret; you must beware of them! St. Ignatius of Antioch

Whoever is separated from the Church must be avoided and fled from; such a man is wrong-headed; he is a sinner and self-condemned. [...] But if some of the leaders of schism persist in their blind and obstinate foolishness, and if advice for their own good fails to bring them back to the way of salvation, let the rest of you [...] break away from their ensnaring falsehood. [...] One must withdraw from those who are engaged in sin; rather, one must fly from them, lest by joining in their evil course and thus taking the wrong road, one should [...] become involved in the same guilt oneself. St. Cyprian

ASSOCIATION WITH HERETICS DEADLY

We have heard that many, saying they are Catholic, are living a life in common with Jews and pagans [...] in diverse errors, maintaining that they are not being harmed. [...] A great and deadly error! Pope Adrian I

I grieve for having been, if only for an hour, in communion with guilty men. St. Martin of Tours

It is an illusion to seek the company of sinners on the pretence of reforming them or of converting them; it is far more to be feared that they will spread their poison to us. St. Gregory Nazianzen

Do not converse with heretics even for the sake of defending the faith, for fear lest their words instil their poison in your mind. Bl. Isaias

For if they have doctrines opposed to ours, it is not fitting to be mixed up with them for this cause alone. [...] What do you say? "Their faith is the same; these men are orthodox"? Why, then, are they not with us? St. John Chysostom

It is therefore unlawful, and a profanation, and an act the punishment of which is death, to love to associate with unholy heretics, and to unite yourself to their communion. St. Cyril of Alexandria

But if you embrace the errors of these nations that dwell among you, and make marriages with them, and join friendships, know ye for a certainty that [...] they shall be a snare and a pit in your way, and a stumbling-block at your side, and stakes in your eyes, til the Lord your God take you away and destroy you. Josue 23:13

You help the ungodly, and you are joined in friendship with those who hate the Lord; and therefore you did indeed deserve the wrath of the Lord. II Paralipomenon 19:2

The accursed perversity of heretics [...] has so increased that now they exercise their wickedness not in secret, but manifest their error publicly, and win over the weak and simple-minded to their opinion. For this reason, We resolve to cast them, their defenders, and their receivers under anathema, and We forbid under anathema that any one presume to help heretics or to do business with heretics. III Lateran Council

NO SOCIAL LIFE WITH HERETICS

Saints Peter and Paul, in their Epistles, have loathed heretics, and warned us to avoid them. St. Cyprian

St. Paul commands that a heretic be avoided after two warnings, that is, after showing himself to be manifestly obstinate. And this is what St. Jerome writes, adding that other sinners are excluded from the Church by excommunication, whereas heretics exile themselves on their own from the Body of Christ. St. Robert Bellarmine

Outside are dogs. Apocalypse 22:13

What fellowship does a holy man have with a dog? Ecclesiasticus 13:22

Or what fellowship does light have with darkness? And what concord does Christ have with Belial? Or what part do the faithful have with the unbeliever? [...] Wherefore, go out from among them and be ye separate, says the Lord. II Corinthians 6:14-17

Separate yourself from your enemies. Ecclesiasticus 6:13

I have always regarded the Church's enemies as my own. St. Jerome

Heresy is everywhere an enemy to Catholics. St. Gregory of Tours

If any man who is called a brother be a servant of idols, with such a man do not keep company, not so much as to eat. I Corinthians 5:11

I will not communicate with the choicest of them. [...] Depart from me, ye malignant ones! Psalm 140:4; 118:115

John, the disciple of the Lord, going to bathe at Ephesus, and finding Cerinthus inside, rushed out of the bath-house without bathing, shouting: "Let us fly, lest even the bath-house fall down, for Cerinthuis, an enemy of truth is inside!" And Polycarp himself replied to Marcion who met him on one occasion asking: "Do you know me?" "I do know you," replied Polycarp: "I know you to be the first-born of Satan!" Such was the horror which the Apostles and their disciples had against even holding even verbal communication with any corrupters of truth. St. Irenaeus of Lyons

OUR OWN FAMILIES TO BE HATED

It is fitting, therefore, that you keep aloof from such persons. and neither in private nor in public speak to them. But flee from all abominable heresies and those who cause schism as the beginning of evils. For as many as are of Christ are also with the bishop, but as many as fall away from Christ embrace communion with the accursed, and shall be cut off along with them. [...] Brethren, do not be deceived. If any man follows him who separates from the truth, he shall not inherit the kingdom of God; and if any man does not stay away from the preacher of falsehood, he shall be condemned to hell. [...] If anyone walks according to a foreign doctrine, he is not of Christ nor a partaker of His passion. Have no fellowship with such a man, lest you perish along with him, even though he should be your father, your son, your brother, or a member of your family. St. Ignatius of Antioch

In respect to their guilt whereby they are opposed to God, all sinners are to be hated, even one's father or mother or kindred, according to Luke 14:26. For it is our duty to hate in the sinner his being a sinner. St. Thomas Aquinas

If any man hate not his father, and mother, and wife, and children, and brothers and sisters [...] he cannot be My disciple. St. Luke 14:26

If any man come to you and bring not this doctrine, receive him not into the house, nor say to him: "God speed you." For he who says to him "God speed you" communicates with his wicked works. II John 1:10-11

When our friends fall into very great wickedness, and become incurable, we ought no longer to show them friendliness. It is for this reason that both divine and human laws command such sinners to be put to death, because there is a greater likelihood of their harming others than of their mending their ways. St. Thomas Aquinas

NO FRIENDSHIP WITH PROTESTANTS

If you will not return to the good path from which you have departed, we shall treat you as a stranger, and we shall separate from you; for it behooves us not to have any communication with one who has abandoned his God to please men and to secure for himself the perishable things of this life, which will cause him to perish everlastingly. St. James Intercisus

If you are friendly with someone who happens to fall into the temptation of fornication, offer him your hand, if you can, to deliver him from it. But if he falls into heresy, and you cannot persuade him to turn from it, separate yourself quickly from him, in case, should you delay, you might also be dragged down with him into the pit. Ven. Matoes the Abbot

If any man shall be friendly to those with whom the Roman Pontiff is not in communion, he is in complicity with those who want to destroy the Church of God; and, although he may seem to be with us in body, he is against us in mind and spirit, and is a much more dangerous enemy than those who are outside and are our avowed foes. Pope St. Clement I

Therefore, be ye not partakers with the children of unbelief. [...] And have no fellowship with the unfruitful works of darkness, but rather reprove them. Ephesians 5:7,11

I have hated the unjust. Psalm 118:113

Let us hate those who are worthy of hatred. Let us withdraw from those from whom God withdraws. Let us say to God with all boldness concerning all heretics: "Do I not hate them, O Lord, who hate Thee?" St. Cyril of Jerusalem

Have I not hated them, O Lord, who hated Thee? [...] I have hated them with a perfect hatred, and they have become enemies to me. Psalm 138:21-22

THE NATURE OF CHRISTIAN WARFARE

We are not faithful to God if we love His enemies. St. Thomas Aquinas

He who can never love Christ enough will never give up fighting against those who hate him. St. John Chysostom

The living God has charged me to declare unto you that He will punish those who will not avenge Him against His enemies. St. Bernard

Joined in friendship with those who hate the Lord, you truly deserve the wrath of God! II Paralipomenon 19:2

I pray God that some of us, as high as we seem to sit treading heretics under our feet like ants, that we live not to see the day we would gladly wish to be at league and composed with them, to let them have their churches quietly to themselves so that they would be content to let us have our quietly to ourselves. [...] Upon conditions that all heresies were suppressed, I would wish that all my books were burned up and all my labour utterly lost. St. Thomas More

So great is my aversion for the company of heretics, or of conversation with them, that I say we ought not even go near them. St. Anthony the Abbot

St. Anthony the Abbot would not speak to a heretic, except to exhort him to the true faith; and he drove all heretics from his mountain, calling them venomous serpents. St. Athanasius

I was to either convert hypocrites to the way of salvation, or reject them and refrain from associating with them. St. Boniface

I entreat you to shun, whenever possible, the society of those who profess false doctrines. St. John Eudes

All our safeguards are of little avail against the ills that threaten us. Suffice it that we have the joy of belonging to the family of God. Bl. Charles the Good

OUR TRUE BROTHERHOOD

Above the brotherhood of humanity and fatherland, there is a brotherhood infinitely more sacred and precious, the brotherhood which makes us one in Christ, namely: our kinship in the Catholic Church, the Mystical Body of Christ Himself. Pope Pius XI

"Blessed are the peacemakers, for they shall be called the children of God" (Matthew 5:9). The "peacemakers" are those who, keeping aloof from the scandal of dissention and discord, preserve the love of fraternal charity and the peace of the Church under the unity of the Catholic faith. [...] For there is nothing so necessary to the servants of God and so salutary to the Church as to keep charity and to love peace, without which, as the Apostle says to the Hebrews, no man can see God. St. Chromatius

Therefore, he, who would not continue as one with the brethren, having followed heretics, goes forth as an antichrist. St. Optatus of Milevis

One might properly and truly say that there is a Church of Evil-doers, that is, the assemblies of the heretics. [...] For this reason, the true faith has already delivered to you, by way of safe-guard, the Article: "And One Holy Catholic Church" in order that you may fly from their meetings, and for the rest of your entire life to remain steadfast in the Holy Catholic Church. St. Cyril of Jerusalem

And we charge you, brethren, in the name of Our Lord Jesus Christ, that you withdraw yourselves from every brother walking disorderly and not according to the tradition which they have received from us. [...] And if any man does not obey our word by this Epistle,. note that man, and do not keep company with him, that he may be ashamed. II Thessalonians 3:6,14

Therefore, if by the sin of Judas, all the Apostles were put in danger, let us by this warning be on our guard against the unbelieving and against the traitor. [...] And let us also drive such a person out of our little ship, so that [...] while the Lord keeps watch no storm of iniquity shall strike us. St. Ambrose

But because you would not stay away from that wicked excommunicated person, you yourself shall die! St. Cedd of London

PRAYER WITH NON-CATHOLICS FORBIDDEN

Are heretics and schismatics excommunicated? Yes; they have no part in the Communion of the Saints. Catechism of the Summa

If any ecclesiastic or layman shall go into the synagogue of the Jews or to the meeting-houses of the heretics to join in prayer with them, let them be deposed and deprived of communion. If any bishop or priest or deacon shall join in prayer with heretics, let him be suspended from communion. II Council of Constantinople

That Christians and ecclesiastics should pray for Christian unity under the direction of heretics and, what is worse, according to an intention which is radically impregnated and vitiated with heresy, is absolutely impossible to tolerate! Ven. Pope Pius XI

One must neither pray nor sing psalms with heretics, and whoever shall communicate with those who are cut off from the communion of the Church, whether clergy or layman: let him be excommunicated. Council of Carthage

No one shall pray in common with heretics and schismatics. Council of Laodicea

Since you are not of my religion, I ought not to join in prayer with you; but I will pray heartily for you: that God would enlighten you, bring you back to His Church, and dispose you for His mercy. Ven. Henry Walpole

I will not pray with you, nor shall you pray with me; neither will I say "Amen" to your prayers, nor shall you to mine! St. Margaret Clitherow

I refuse to pray with you, but I desire all Catholics to pray for me, and I mean Catholics of the Catholic Roman Church. Ven. George Haydock

We decree that those who give credence to the teachings of the heretics, as well as those who receive, defend or patronize them, are excommunicated. [...] If anyone refuses to avoid such accomplices after they have been ostracized by the Church, let them also be excommunicated. IV Lateran Council

FLY FROM PROTESTANT CHURCHES

It is not right that one who has been condemned and cast out by the Apostolic See of Rome for his wrong opinions should be named with any kind of honour until he be received by her, having returned to her by a pious confession and orthodox faith. St. Maximus of Constantinople

You have no right to receive a heretic into your communion. Pope St. Simplicius

Therefore, receive into communion those who teach and think as I do; but refuse those who are otherwise minded, and hold them as strangers to God and to the Catholic Church. St. Gregory Nazianzen

In the celebration of the sacred mysteries, there should not be recited the names of those who have been separated from communion with the Catholic Church. III Council of Constantinople

Put away the evil one from among yourselves. I Corinthians 5:13

Cut off the decayed flesh, expel the mangy sheep from the fold, lest the whole house, the whole paste, the whole body, the whole flock, burn, perish, rot and die! St. Jerome

These men are Protestants; they are heretics! Have nothing to do with them! St. Anthony Mary Claret

I will live and die in the true Roman Catholic faith, which I and all antiquity have always professed; and I will by no means go to Protestant churches. Ven. Edmund Genings

It is not lawful to go to the Protestant church. St. John Rigby

Abhor schism, and adhere to the Catholic Church! St. Hippolytus of Rome

HERETICS TO BURN AT THE STAKE

With regard to heretics, two arguments must be observed: one concerning themselves, the other from the aspect of the Church. On their own side, there is the sin whereby they deserve to be separated from the Church by excommunication, but also to be severed from the world by death. For it is a much more serious matter to corrupt the faith which gives life to the soul than to counterfeit that which supports temporal life. Wherefore, if counterfeiters and other evil-doers are immediately condemned to death by the secular authorities, there is much more reason for heretics, as soon as they are convicted of heresy, not only to be excommunicated but even put to death. On the part of the Church, however, there is mercy, which looks to the conversion of the wanderer; wherefore, she condemns not at once, but "after the first and second warning", as the Apostle directs (Titus 3:10). After that, if he is still stubborn, the Church, no longer hoping for his conversion, looks to the salvation of others by excommunicating him and separating him from the Church; and, furthermore, she delivers him over to the secular tribunal, thereby to be exterminated from the world by death. St. Thomas Aquinas

I entirely detest heretics, and as Magistrate do promise assiduously to perform my duty in investigating them. Heresy is a kind of treason, and if a heretic persisteth in his false belief, he may be handed over to be burned. St. Thomas More

Error will never be suppressed unless the criminal elements of depravity be consumed in flames. Pope Clement XII

If you were a heretic, you would go to the stake. St. Ignatius of Loyola

Christ did not forbid us to reprove heretics, to silence their mouths, to restrict their liberty of speech, to scatter their assemblies. [...] When they have not profited from the forbearance of the Lord, they must then receive their inevitable chastisement. St. John Chysostom

If heretics be altogether uprooted by death, this is not contrary to Our Lord's command. St. Thomas Aquinas

That it is against the will of the Spirit to burn heretics at the stake is condemned as false. Pope Leo X

The Holy Roman Catholic Church condemns, disapproves, anathematizes, and declares to be separated from the Body of Christ, which is the Church, everyone who holds any contrary opinions. Council of Florence

NO PEACE WITH WORLDLINGS

It is a blessing when such men break away from the Church: it prevents them preying upon the doves and sheep of Christ with their savage and poisonous influence. It is impossible to join and combine the bitter with the sweet, darkness with light, rain with fair weather, war with peace; nor sterility with fertility, aridity with springs of water, or a storm with a calm. St. Cyprian

Make no mistake, my brethren, they shall suffer everlasting punishment who endeavour to corrupt the Church of Christ. Whosoever sets at nought His doctrine shall go into Hell, and so shall everyone who listens to him. [...] What communion does light have with darkness, or Christ with Belial? Or what portion does truth have with falsehood? Or unrighteousness with unrighteousness? Or true doctrine with that which is false? St. Ignatius of Antioch

There is no concord between the love of this world and the love of God; and he who will not separate himself from the children of this world shall not belong to the children of God. Pope St. Leo the Great

He who loves father or mother more than Me is not worthy of Me, and he who loves son or daughter more than Me is not worthy of Me. St. Matthew 10:37

I should not think of any relatives other than the saints in Heaven. St. Phileas of Thmuis

For if faith be injured, let honour due to parents be lost as stale and tottering; let even the law of tender love towards children and brothers be silenced! St. Cyril of Alexandria

I beseech you, brethren, to mark those who make dissentions and offenses contrary to the doctrine which you have learned and to avoid them. Romans 16:17

The Church says: "Cast out heresies and their children; for heretics shall not be heirs with Catholics!" Why can they not be heirs? [...] Have they not put on the Baptism of the Church? They do have Baptism [...] by the same word and Sacrament in which you were born. But they will not come to the same inheritance of eternal life unless they return to the Catholic Church. St. Augustine

ALL HERETICS TO BE SHUNNED

A man who is a heretic, after the first and second admonition avoid: knowing that such a man is subverted and sins, being condemned by his own judgement. St. Titus 3:10-11

Turn your thoughts away from a non-Catholic, turn away your ears, so that you may have strength to grasp life everlasting through the one, true and holy Catholic Church. Our Lord warns all the faithful: they must not put any faith in heretics or schismatics. St. Augustine

Saint Anthony's devotion to the faith was wonderful. He never held communion with the Meletian schismatics, knowing their wickedness and rebellion from the beginning; neither did he have friendly converse with the Manichees or any other heretics, except only to warn them to return to their duty, believing and teaching that their friendship and society was harmful and ruinous to the soul. Thus also he loathed the Arian heresy, and taught all men neither to go near them nor to partake in their bad faith. Once, when some of the Ariomanites came to him and he questioned them and found them to be misbelievers, he drove them from the hill, crying that their words were worse than the venom of serpents. St. Athanasius

Do not treat with a man without religion. [...] Give no heed to them in any matter of counsel. Ecclesiasticus 37:12,14

Indeed, why should I care for the opinions of a Pagan on matters which are among the chief mysteries of the Christian faith? St. Thomas More

Men who are holy are separated with their whole heart and by the eagerness of their faith from evil-doers; and they shall be completely separated from them in the future. St. Thomas Aquinas

Separation from the Elect necessarily implies the loss of eternal salvation, and therefore damnation, since there is no middle between them. St. Alphonsus Maria Liguori

It is impossible for us to hold communion after their death with those who have not been in communion with us during their life. Pope Innocent III

NO HOLY EUCHARIST FOR PROTESTANTS

With all our strength, therefore, let us guard against receiving Communion from heretics and from giving Communion to them. "Do not give that which is holy to dogs," the Lord says, "nor cast your pearls before swine." St. John Chysostom

I would rather give up life itself first than to communicate the Blood of the Lord to those who are unworthy. St. John Chrysostom

We should anathematize heretics even after their death. II Council of Constantinople

What hath chaff to do with the wheat? saith the Lord. Jeremias 23:28

I cannot communicate with unclean heretics even by a single word! St. Paphnutius

Since these wretched souls will have to be separated from God and Heaven for all eternity because their place will be in Hell, already here on earth they have to be separated from the company of Christ Our Lord and His servants and hand-maids. Predestinate souls, you who are of God, cut yourselves adrift from those who are damning themselves! Saint Louis Marie de Montfort

Do everything you can to break away from such men; as you value your salvation, avoid those who associate with such harmful connections. [...] Their talk spreads like cancer, their conversation is as catching as an infection [...] their poisonous and pernicious propaganda is more deadly than persecution was. Persecution leaves the door open to penance and satisfaction; but those who do away with penance for sin shut the door against satisfaction altogether. And so it is that, through the presumption of certain people who beguile themselves with false promises of salvation, all true hope of salvation is destroyed. St. Cyprian

We have become cowardly, faint-hearted, and, so often, for some reason or other, we keep silence. We let ourselves be overcome by human respect, and cease to show ourselves as true followers of Our Lord before the world. [...] Why? Because we are cowards! Oh, how we need to renew our faith, to rekindle our hearts in the sublime principles of our holy religion! St. Frances Xavier Cabrini

WE MUST FIGHT FOR THE FAITH

Give thanks to God that He has made you a child of His Church which is always animated and governed by His Divine Spirit Who was sent into the world on the day of Pentecost. Hear and follow the Sovereign Pontiff who teaches infallibly through the Holy Ghost and the Church, which is the pillar and ground of truth. Hold fast to Her doctrines, maintain Her cause, defend Her rights. Live always as becomes a child of God and a member of the true Church of God, so that after this life you may receive Heaven as your inheritance. Glory be to the Father, and to the Son, and to the Holy Ghost! Amen. Pope St. Pius X

References:

Pius XI: Mortalium Animos

Leo XIII: Hortus Conclusus

Thomas Aquinas: On Matthew, 7:15; Summa Theologica ii-ii, q.10. article 10.

Deuteronomy: op. cit.

Matthew: op. cit.

Origen: On Exodus

IV Lateran:

Pius XI: op.cit.

Laodicea: canon two

Leo the Great: De Jejun. Pent.

Corinthians: op. cit.

Arnobius: Commentary on psalm 128

Ignatius: Epistle to the Ephesians

Cyprian: Unity of the Catholic Church nos. 17 and 23

Adrian I: Instituio Universalis

Martin: The Life of Martin, St. Supplicius severus.

Gregory: cf. Sunday Sermons of the Great Fathers.

Isaias: Oration 4:6

John: On Leviticus 17:3

Josue op. cit.

Paralipomenon: op. cit.

III Lateran: Heresies to be Avoided, ch. 27

Cyprian: Epistle 75

Robert: On the Church Militant

Apocalypse: op. cit.

Ecclesiasticus: op. cit.

Corinthians: op. cit.

Ecclesiasticus: op. cit.

Jerome:

Gregory:

Corinthians: op. cit.

Psalm: op. cit.

Irenaeus: Against Heresies, Bk. 3, ch. 3:4 and 4:1

Ignatius: Epistle to Philadelphians

Thomas Aquinas: op. cit. ad 2

James: Victories of the Martyrs, St. Alphonsus Maria Liguori

Theodore:

Matoes:

Clement I: Epistle to the Corinthians

Ephesians: op. cit.

Psalm: op. cit.

Cyril: Catechetical Lectures

Psalm: op. cit.

Thomas Aquinas: Summa Theologica

John: The Great Commentary of Cornelius Lapide 3:44

Bernard: cf. Sermons

Paralipomenon: op. cit.

Thomas More: Apologye

Anthony: Divine Office, The Liturgical Year, Don Prosper Gueranger, O.S.B., 3:308

Athanasius: St. Anthony the Hermit, St. Athanasius

Boniface:

John Eudes:

Charles:

Pius XI: Mortalium Animos

Chromatius: On the Gospel of Matthew, tract 7

Optatus: On the Schism of the Donatists 1:15

Cyril: Catechetical Lectures 18:25

Thessalonians: op. cit.

Ambrose: The Two Ships, 7, Sermon 37

Cedd:

Catechism: Catechism of the Summa Theologica of Saint Thomas Aquinas, Fr. Thos. Peques, O.P.

III Constantinople

Pius IX:

Carthage:

Laodices:

Henry:

Margaret:

George:

IV Lateran:

Maximus:

Simplicius:

Gregory:

III Constantinople:

Corinthians: op. cit.

Jerome: On Galatians 5:9, cited in Summa Theologica II-II Q.11, art. 3

Anthony Mary:

Edmund:

John Rigby:

Hyppolytus:

Thomas Aquinas: Summa Theologica II-II Q.11. art. 3

Thomas More: Debellacyon of Salem and Bizance

Clement XII: Christianae, quoted by Pope Gregory XVI in Mirari Vos

Ignatius:

John:

Thomas Aquinas: Summa Theologica II-II Q.11, art. 3, ad 3

Leo X: Exsurge Domine

Florence: Decree for the Jacobites

Cyprian: The Unity of the Catholic Church

Ignatius: Epistle to the Ephesians, ch. 15

Leo the Great: On the Beatitudes, Homily 95, ch.9

Matthew: op. cit.

Phileas: Victories of the Martyrs, St. Alphonsus Maria Liguori, 115

Cyril: Romans: op. cit.

Augustine: Sermon 3

Titus op. cit.

Augustine:

Athanasius: Saint Anthony the Hermit, Saint Athanasius

Ecclesiasticus: op. cit.

Thomas More: Lucianas Opuscula

Thomas Aquinas: Catena Aurea

Alphonsus Maria:

Innocent III

John Damascene: The Source of knowledge 3, 4:14

John Chysostom: Respect Due the Church and the Sacred Mysteries

II Constantinople:

Jeremias: op. cit.

Paphnutius: Cornelius Lapide

Louis Marie: Secret of the Rosary, 99

Cyprian: Unity of the Catholic Church

Frances:

Pius X: