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"The practice of the Church has always been the same, as is shown by the unanimous teaching of the Fathers, who were wont to hold as outside Catholic communion, and alien to the Church, whoever would recede in the least degree from any point of doctrine proposed by her authoritative Magisterium. Epiphanius, Augustine, Theodoret, drew up a long list of the heresies of their times. St. Augustine notes that other heresies may spring up, to a single one of which, should any one give his assent, he is by the very fact cut off from Catholic unity. "No one who merely disbelieves in all (these heresies) can for that reason regard himself as a Catholic or call himself one. For there may be or may arise some other heresies, which are not set out in this work of ours, and, if any one holds to one single one of these he is not a Catholic" (S. Augustinus, De Haeresibus, n. 88)." (Pope Leo XIII, Satis Cognitum, 1896). [Therefore, all heretics are alien to the Church, and are not Catholic, including all of the apostate bishops, false cardinals, and false Antipopes like Francis that have approved and endorsed the wicked Vatican II council].

“No one, therefore, unless in communion with Peter can share in his authority, since it is absurd to imagine that he who is outside can command in the Church.” (Pope Leo XIII, Satis Cognitum (#15), June 29, 1896).  [Therefore, no heretic or apostate, including everyone who approved the Vatican II council, can command or have authority in the Catholic Church].




Vatican II Declaration, Nostra Aetate (#4): “Although the Church is the new people of God, the Jews should not be presented as rejected or cursed by God, as if such views followed from the holy scriptures.”

“Therefore it [the Church] condemns, rejects, anathematizes and declares to be outside the Body of Christ, which is the Church, whoever holds opposing or contrary views.” (Pope Eugene IV, Council of Florence, 1442 A.D.)

“Therefore the Catholic Church denounces all who after that time observe circumcision, the sabbath and other such legal prescriptions [the Jews] as strangers to the faith of Christ and unable to share in eternal salvation.”(Pope Eugene IV, Council of Florence, Bull of Union with the Copts, 1442 A.D.)


Vatican II, Unitatis Redintegratio #3: “For men who believe in Christ and have been truly baptized are in communion with the Catholic Church even though this communion is imperfect. The differences that exist in varying degrees between them and the Catholic Church- whether in doctrine and sometimes in discipline, or concerning the structure of the Church- do indeed create many obstacles, sometimes serious ones, to full ecclesiastical communion. The ecumenical movement is striving to overcome these obstacles. But even in spite of them it remains true that all who have been justified by faith in Baptism are incorporated into Christ, and have a right to be called Christian, and so are correctly accepted as brothers by the children of the Catholic Church.”

Pope Leo XIII, Satis Cognitum (# 9), June 29, 1896: “The practice of the Church has always been the same, as is shown by the unanimous teaching of the Fathers, who were wont to hold as outside Catholic communion, and alien to the Church, whoever would recede

in the least degree from any point of doctrine proposed by her authoritative Magisterium.”


Vatican II document, Unitatis redintegratio (# 4):

“Nevertheless, the divisions among Christians prevent the Church from realizing in practice the fullness of Catholicity proper to her, in those of her sons and daughters who, though attached to her by baptism, are yet separated from full communion with her.  Furthermore, the Church herself finds it more difficult to express in actual life her full Catholicity in all its bearings.”

Pope Clement VI, Super quibusdam, Sept. 20, 1351:

“We ask: In the first place, whether you and the Church of the Armenians which is obedient to you, believe that all those who in baptism have received the same Catholic faith, and afterwards have withdrawn and will withdraw in the future from the communion of THIS SAME ROMAN CHURCH, WHICH ONE ALONE IS CATHOLIC, are schismatic and heretical, if they remain obstinately separated from the faith of this Roman Church.”

“I believe in the Catholic Church, the communion of saints, the forgiveness of sins, the resurrection of the body, and the life everlasting” (Dogmatic Apostle’s Creed)


Vatican II document, Unitatis redintegratio (# 3):

“It follows that these separated churches and communities as such, though we believe them to be deficient in some respects, have by no means been deprived of significance and importance in the mystery of salvation. For the Spirit of Christ has not refrained from using them as means of salvation whose efficacy comes from that fullness of grace and truth which has been entrusted to the Catholic Church.”

Pope St. Pius X, Editae saepe (# 29), May 26, 1910: “The Church alone possesses together with her magisterium the power of governing and sanctifying human society. Through

her ministers and servants (each in his own station and office), she confers on mankind suitable and necessary means of salvation.”

Pope Eugene IV, Council of Florence, “Cantate Domino,” 1441:

The Holy Roman Church firmly believes, professes and preaches that all those who are outside the Catholic Church, not only pagans but also Jews or heretics and schismatics, cannot share in eternal life and will go into the everlasting fire which was prepared for the devil and his angels, unless they are joined to the Church before the end of their lives


Vatican II document, Unitatis redintegratio # 4:

“On the other hand, Catholics must gladly acknowledge and esteem the truly Christian endowments which derive from our common heritage and which are to be found among our separated brothers and sisters. It is right and salutary to recognize the riches of Christ and the virtuous deeds in the lives of others who bear witness to Christ, even at times to the shedding of their blood.”

John Paul II, Ut Unum Sint (# 1), May 25, 1995:

“The courageous witness of so many martyrs of our century, including members of Churches and Ecclesial Communities not in full communion with the Catholic Church, gives new vigor to the Council’s call and reminds us of our duty to listen to and put into practice its exhortation.”

John Paul II, Ut Unum Sint (# 84), May 25, 1995:

“Albeit in an invisible way, the communion between our Communities, even if still incomplete, is truly and solidly grounded in the full communion of the saints - those who, at the end of a life faithful to grace, are in communion with Christ in glory. These saints come from all the Churches and Ecclesial Communities which gave them entrance into the communion of salvation.”

Pope Pelagius II, epistle (2) Dilectionis vestrae, 585:

“Those who were not willing to be at agreement in the Church of God, cannot remain with God; although given over to flames and fires, they burn, or thrown to wild beasts,they lay down their lives, there will not be for them that crown of faith, but the punishment of faithlessness, not a glorious result (of religious virtue), but the ruin of despair. Such a one can be slain; he cannot be crowned.”

Pope Eugene IV, Council of Florence, Cantate Domino, Session 11, Feb. 4, 1442:

“… no one, whatever almsgiving he has practiced, even if he has shed blood for the name of Christ, can be saved, unless he has remained within the bosom and unity of the Catholic Church.”


Vatican II document, Unitatis redintegratio [On the Eastern Schismatics] (#’s 13-15):

“We now turn our attention to the two chief types of division as they affect the seamless robe of Christ. The first division occurred in the east, when the dogmatic formulas of the councils of Ephesus and Chalcedon were challenged, and later when ecclesiastical communion between the eastern patriarchates and the Roman See was dissolved… Everyone knows with what great love the Christians [Eastern heretics and schismatics] of the east celebrate the sacred liturgy… Hence, through the celebration of the Holy Eucharist in each of these [eastern heretical and schismatic] Churches, the Church of God is built up and grows, and through concelebration their communion with one another is made manifest.”

Pope Vigilius, Second Council of Constantinople, 553:

“These matters having been treated with thorough-going exactness, we bear in mind what was promised about the holy Church and Him who said the gates of hell will not prevail against it .  By these we understand the death-dealing tongues of heretics… and

so we count along with the devil, the father of lies, the uncontrolled tongues of heretics and their heretical writings, together with the heretics themselves who have persisted in

their heresy even to death.”

Pope St. Leo IX, In terra pax hominibus, Sept. 2, 1053, to the “Father” of the Eastern Orthodox, Michael Cerularius, Chap. 7: “The holy Church built upon a rock, that is Christ, and upon Peter or Cephas, the son of John who first was called Simon, because by the gates of Hell, that is, by the disputations of heretics which lead the vain to destruction, it would never be overcome.”


Vatican II document, Unitatis redintegratio # 3:

“But in subsequent centuries much more extensive dissensions made their appearance and large communities came to be separated from the full communion of the Catholic Church – for which, often enough, both sides were to blame. The children who are born into these Communities and who grow up believing in Christ cannot be accused of the sin involved in the separation, and the Catholic Church embraces them as brothers, with

respect and affection.”

Pope Innocent III, Fourth Lateran Council, 1215, Constitution 3, On Heretics:

We excommunicate and anathematize every heresy raising itself up against this holy, orthodox and Catholic faith which we have expounded above. We condemn all heretics, whatever names they may go under. They have different faces indeed but

their tails are tied together in as much as they are alike in their pride.”

Pope Pelagius II, epistle (1) Quod ad dilectionem, 585:

“If anyone, however, either suggests or believes or presumes to teach contrary to this faith, let him know that he is condemned and also anathematized according to the opinion of the same Fathers.

First Council of Constantinople, 381, Can. 1:

Every heresy is to be anathematized and in particular that of the Eunomians or Anomoeans, that of the Arians or Eudoxians, that of the Semi-Arians or Pneumatomachi, that of the Sabellians, that of the Marcellians, that of the Photinians and that of the


Pope Pius XI, Rerum omnium perturbationem (# 4), Jan. 26, 1923: “… the heresies begotten by the [Protestant] Reformation. It is in these heresies that we discover the beginnings of that apostasy of mankind from the Church, the sad and disastrous effects of which are deplored, even to the present hour, by every fair mind.”


Vatican II document, Unitatis redintegratio # 9:

“We must get to know the outlook of our separated fellow Christians… Most valuable for this purpose are meetings of the two sides – especially for discussion of theological problems – where each side can treat with the other on an equal footing, provided that those who take part in them under the guidance of their authorities are truly competent.”

Pope Pius XI, Mortalium Animos (# 7), Jan. 6, 1928, speaking of heretics:

“Meanwhile they affirm that they would willingly treat with the Church of Rome, but on equal terms, that is as equals with an equal...”


Vatican II document, Orientalium Ecclesiarum # 27:

“Given the above-mentioned principles, the sacraments of Penance, Holy Eucharist, and the anointing of the sick may be conferred on eastern Christians who in good faith are separated from the Catholic Church, if they make the request of their own accord and are properly disposed.”

John Paul II, General Audience, Aug. 9, 1995:

“Concerning aspects of intercommunion, the recent Ecumenical Directory confirms and states precisely all that the Council said: that is, a certain intercommunion is possible, since the Eastern Churches possess true sacraments, especially the priesthood and the Eucharist.  On this sensitive point, specific instructions have been issued, stating that, whenever it is impossible for a Catholic to have recourse to a Catholic priest, he may receive the sacraments of Penance, the Eucharist and the Anointing of the Sick from the minister of an Eastern Church (Directory, n. 123). Reciprocally, Catholic ministers may licitly administer the sacraments of Penance, the Eucharist and the Anointing of the Sick to Eastern Christians who ask for them.”

John Paul II, Ut Unum Sint (# 48), May 25, 1995:

“Pastoral experience shows that with respect to our Eastern brethren there should be and can be taken into consideration various circumstances affecting individuals, wherein the unity of the Church is not jeopardized nor are intolerable risks involved, but in which salvation itself and the spiritual profit of souls are urgently at issue. Hence, in view of special circumstances of time, place and personage, the Catholic Church has often adopted and now adopts a milder policy, offering to all the means of salvation and an example of charity among Christians through participation in the sacraments and in other sacred functions and objectsThere must never be a loss of appreciation for the ecclesiological implication of sharing in the sacraments, especially the Holy Eucharist.”

Vatican II document, Orientalium Ecclesiarum # 28:

“With the same principles in mind, sharing in sacred functions and things and places is allowed among Catholics and their separated eastern brothers and sisters...”

Pope Boniface VIII, Unam Sanctam, Nov. 18, 1302:

“With Faith urging us we are forced to believe and to hold the one, holy, Catholic Church and that, apostolic, and we firmly believe and simply confess this Church outside of which there is no salvation nor remission of sin, the Spouse in the Canticle proclaiming: ‘One is my dove, my perfect one.’”

Pope Eugene IV, Council of Florence, “Cantate Domino,” 1441, ex cathedra: The Holy Roman Church firmly believes, professes and preaches that all those who are outside the Catholic Church, not only pagans but also Jews or heretics and schismatics, cannot share in eternal life and will go into the everlasting fire which was prepared for the devil and his angels, unless they are joined to the Church before the end of their lives; that the unity of this ecclesiastical body is of such importance that only for those who abide in it do the Church’s sacraments contribute to salvation and do fasts, almsgiving and other works of piety and practices of the Christian militia produce eternal rewards; and that nobody can be saved, no matter how much he has given away in alms and even if he has shed blood in the name of Christ, unless he has persevered in the bosom and unity of the Catholic Church.”

Pope Pius VIII, Traditi Humilitati (# 4), May 24, 1829:

“Jerome used to say it this way: he who eats the Lamb outside this house will perish as did those during the flood who were not with Noah in the ark.”

Pope Gregory XVI, Commissum divinitus (# 11), May 17, 1835:

“… whoever dares to depart from the unity of Peter might understand that he no longer shares in the divine mystery…‘Whoever eats the Lamb outside of this house is unholy.’”

Pope Pius IX, Amantissimus (# 3), April 8, 1862:

“… whoever eats of the Lamb and is not a member of the Church, has profaned.”


Vatican II document, Orientalium Ecclesiarum # 30:

“They should also pray that the fullness of the strength and solace of the holy Spirit, the Paraclete, may flow out upon those many Christians of any Church whatsoever who, fearlessly confessing Christ, are undergoing suffering and distress.”

Pope Leo XII, Ubi Primum (# 14), May 5, 1824:

It is impossible for the most true God, who is Truth itself, the best, the wisest Provider, and the Rewarder of good men, to approve all sects who profess false teachings which are often inconsistent with one another and contradictory, and to confer eternal

salvation on their members… by divine faith we hold one Lord, one faith, one baptism… This is why we profess that there is no salvation outside the Church.”

Pope St. Celestine I, Council of Ephesus, 431:

“… remember that the followers of every heresy extract from inspired scripture the occasion of their error, and that all heretics corrupt the true expressions of the holy Spirit with their own evil minds and they draw down on their heads an inextinguishable flame.”


Vatican II document, Lumen Gentium # 22:

“However, the order of Bishops, which succeeds the college of apostles in teaching authority and pastoral government, and indeed in which the apostolic body continues to exist without interruption, is also the subject of supreme and full power over the universal Church, provided it remains united with its head …”

Pope Leo XIII, Satis Cognitum (# 15):

“But the power of the Roman Pontiff is supreme, universal, and definitely peculiar to itself; but that of the bishops is circumscribed by definite limits, and definitely peculiar to themselves.”


Vatican II document, Lumen Gentium # 15:

“For several reasons the Church recognizes that it is joined to those who, though baptized and so honoured with the Christian name, do not profess the faith in its entirety or do not preserve communion under the successor of St. Peter.”

Pope Pius IX, Amantissimus (# 3), April 8, 1862:

“There are other, almost countless, proofs drawn from the most trustworthy witnesses which clearly and openly testify with great faith, exactitude, respect and obedience that all who want to belong to the true and only Church of Christ must honor and obey this

Apostolic See and the Roman Pontiff.”

Pope Pius VI, Charitas (# 32), April 13, 1791:

“Finally, in one word, stay close to Us. For no one can be in the Church of Christ without being in unity with its visible head and founded on the See of Peter.”

Pope Leo XIII, Satis Cognitum (# 9), June 29, 1896:


Pope St. Leo the Great, Sermon 129: “Wherefore, since outside the Catholic Church there is nothing perfect, nothing undefiled… 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.”


Vatican II document, Lumen Gentium # 15, speaking of non-Catholics:

For there are many [heretics] who hold the sacred scripture in honor as the norm for believing and living, displaying a sincere religious zeal… They are marked in baptism… and indeed there are other sacraments that they recognize and accept in their own Churches or ecclesiastical communities.”

Pope Gregory XVI, Inter Praecipuas (# 2), May 8, 1844: “Indeed, you are aware that from the first ages called Christian, it has been the peculiar artifice of heretics that, repudiating the traditional Word of God, and rejecting the authority of the Catholic Church, they either falsify the Scriptures at hand, or alter the explanation of the meaning.


Vatican II document, Dignitatis humanae # 2:

“This Vatican synod declares that the human person has a right to religious freedom.  Such freedom consists in this, that all should have such immunity from coercion by individuals, or by groups, or by any human power, that no one should be forced to act against his conscience in religious matters, nor prevented from acting according to his conscience, whether in private or in public, within due limits… This right of the human

person to religious freedom should have such recognition in the regulation of society as to become a civil right… therefore this right to noninterference persists even in those who do not carry out their obligations of seeking the truth and standing by it; and the exercise of this right should not be curtailed, as long as due public order is preserved..”

Vatican II document, Dignitatis humanae # 3:

“So the state, whose proper purpose it is to provide for the temporal common good, should certainly recognize and promote the religious life of its citizens. With equal certainty it exceeds the limits of its authority, if it takes upon itself to direct or to prevent religious activity.”

Benedict XVI, Principles of Catholic Theology, 1982, p. 381: "If it is desirable to offer a diagnosis of the text [of the Vatican II document, Gaudium et Spes] as a whole, we might say that (in conjunction with the texts on religious liberty and world religions) it is a revision of the Syllabus of Pius IX, a kind of counter syllabusAs a result, the one-sidedness of the position adopted by the Church under Pius IX and Pius X in response to the situation created by the new phase of history inaugurated by the French Revolution, was, to a large extent, corrected..."

Benedict XVI, Principles of Catholic Theology, 1982, p. 391: " The task is not, therefore, to suppress the Council but to discover the real Council and to deepen its true intention in the light of present experience. That means that there can be no return to the Syllabus, which may have marked the first stage in the confrontation with liberalism and a newly conceived Marxism but cannot be the last stage."

Pope Pius IX, Syllabus of Errors, Dec. 8, 1864, # 77 CONDEMNED THE FOLLOWING:

“In this age of ours it is no longer expedient that the Catholic religion should be the only religion of the state, to the exclusion of all other cults whatsoever.”

Pope Pius IX, Syllabus of Errors, # 78 CONDEMNED THE FOLLOWING:

“Hence in certain regions of Catholic name, it has been laudably sanctioned by law that

men immigrating there be allowed to have public exercises of any form of worship of

their own.”

Pope Pius IX, Syllabus of Errors, Dec. 8, 1864, # 55 CONDEMNED THE FOLLOWING:

“The Church is to be separated from the state, and the state from the Church.”

Pope Pius IX, Quanta Cura (# 3), Dec. 8, 1864:

From which totally false idea of social government they do not fear to foster THAT ERRONEOUS OPINION, most fatal in its effects on the Catholic Church and the



“This shameful font of indifferentism gives rise to that absurd and erroneous proposition which claims that liberty of conscience must be maintained for everyone. It spreads ruin in sacred and civil affairs, though some repeat over and over again with the greatest impudence that some advantage accrues to religion from it. "But the death of the soul is worse than freedom of error," as Augustine was wont to say. When all restraints are removed by which men are kept on the narrow path of truth, their nature, which is already inclined to evil, propels them to ruin. Then truly "the bottomless pit" is open from which John saw smoke ascending which obscured the sun, and out of which locusts flew forth to devastate the earth. Thence comes transformation of minds, corruption of youths, contempt of sacred things and holy laws -- in other words, a pestilence more deadly to the state than any other. Experience shows, even from earliest times, that cities renowned for wealth, dominion, and glory perished as a result of this single evil, namely immoderate freedom of opinion, license of free speech, and desire for novelty. Here We must include that harmful and never sufficiently denounced freedom to publish any writings whatever and disseminate them to the people, which some dare to demand and promote with so great a clamor. We are horrified to see what monstrous doctrines and prodigious errors are disseminated far and wide in countless books, pamphlets, and other writings which, though small in weight, are very great in malice. We are in tears at the abuse which proceeds from them over the face of the earth. Some are so carried away that they contentiously assert that the flock of errors arising from them is sufficiently compensated by the publication of some book which defends religion and truth. Every law condemns deliberately doing evil simply because there is some hope that good may result. Is there any sane man who would say poison ought to be distributed, sold publicly, stored, and even drunk because some antidote is available and those who use it may be snatched from death again and again?” (Gregory XVI, Mirair Vos, 1832).

“There is certainly no need of many words, in addressing you, to make you fully recognize by how lethal a wound the Catholic religion in France is struck by this article. For when the liberty of all "religions" is indiscriminately asserted, by this very fact truth is confounded with error and the holy and immaculate Spouse of Christ, the Church, outside of which there can be no salvation, is set on a par with the sects of heretics and with Judaic perfidy itself. For when favour and patronage is promised even to the sects of heretics and their ministers, not only their persons, but also their very errors, are tolerated and fostered: a system of errors in which is contained that fatal and never sufficiently to be deplored HERESY which, as St. Augustine says (de Haeresibus, no.72), "asserts that all heretics proceed correctly and tell the truth: which is so absurd that it seems incredible to me." (Pope Pius VII, Post Tam Diuturnas, 1814).

Pope Leo XIII, Libertas (# 21-23), June 20, 1888:

Justice therefore forbids, and reason itself forbids, the State to be godless; or to adopt a line of action which would end in godlessness – namely, to treat the various religions (as they call them) alike, and to bestow upon them promiscuously equal rights and privileges. Since, then, the profession of one religion is necessary in the State, that religion must be professed which alone is true, and which can be recognized without difficulty, especially in the Catholic States, because the marks of truth are, as it were, engraven upon it… Men have a right freely and prudently to propagate throughout the State what things soever are true and honorable, so that as many as possible may possess them; but lying opinions, than which no mental plague is greater, and vices which corrupt the heart and moral life should be diligently repressed by public authority, lest they insidiously work the ruin of the State.”

Pope Clement V, Council of Vienne, 1311-1312:

It is an insult to the holy name and a disgrace to the Christian faith that in certain parts of the world subject to Christian princes where Saracens [i.e., the followers of Islam, also called Muslims] live, sometimes apart, sometimes intermingled with Christians, the Saracen priests, commonly called Zabazala, in their temples or mosques, in which the Saracens meet to adore the infidel Mahomet, loudly invoke and extol his name each day at certain hours from a high place… This brings disrepute on our faith and gives great scandal to the faithful. These practices cannot be tolerated without displeasing the divine majesty. We therefore, with the sacred council’s approval, strictly forbid such practices henceforth in Christian lands. We enjoin on Catholic princes, one and allThey are to forbid expressly the public invocation of the sacrilegious name of Mahomet… Those who presume to act otherwise are to be so chastised by the princes for their irreverence, that others may be deterred from such boldness.”

Pope Gregory XVI, Inter Praecipuas (# 14), May 8, 1844: “Experience shows that there is no more direct way of alienating the populace from fidelity and obedience to their leaders than through that indifference to religion propagated by the sect members under the name of religious liberty.”


Vatican II document, Orientalium Ecclesiarum # 30: “They should also pray that the fullness of the strength and solace of the holy Spirit, the Paraclete, may flow out upon those many Christians of any Church whatsoever who, fearlessly confessing Christ, are undergoing suffering and distress.”

Pope St. Celestine I, Council of Ephesus, 431: “… remember that the followers of every heresy extract from inspired scripture the occasion of their error, and that all heretics corrupt the true expressions of the Holy Spirit with their own evil minds and they draw down on their heads an inextinguishable flame.


Vatican II document, Orientalium Ecclesiarum # 28: “With the same principles in mind, sharing in sacred functions and things and places is allowed among Catholics and their separated eastern brothers and sisters…”

“…That false opinion which considers all religions to be more or less good and praiseworthy… from which it clearly follows that one who supports those who hold these theories and attempt to realize them, IS ALTOGETHER ABANDONING the divinely revealed religion So, Venerable Brethren, it is clear why this Apostolic See has NEVER ALLOWED ITS SUBJECTS TO TAKE PART IN THE ASSEMBLIES OF NON-CATHOLICS: for the union of Christians can only be promoted by promoting the return to the one true Church of Christ of those who are separated from it, for in the past they have unhappily left it. - (Pope Pius XI, Mortalium Animos #2, #10, 1928).

“The Catholic Church is alone in keeping the true worship. This is the fount of truth, this the house of Faith, this the temple of God: if any man enter not here, or if any man go forth from it, he is a stranger to the hope of life and salvation.” (Pope Pius XI Mortalium Animos #11)

Pope Pius VI, Charitas Quae (#29-31), April 13, 1791: “Keep as far from you as possible all intrusion and schism... Above all, avoid and condemn the sacrilegious intruders... Keep away from all intruders, whether called archbishops, bishops, or parish priests; do not hold communion with them especially in divine worship.”

Pope Leo XIII, Satis Cognitium (# 9): “There can be nothing more dangerous than those heretics who admit nearly the whole cycle of doctrine, and yet by one word, as with a drop of poison, infect the real and simple faith taught by our Lord and handed down by Apostolic tradition.

II Council Of Constantinople, 680-681: “If any ecclesiastic or layman shall go into the synagogue of the Jews or the meetinghouses of the heretics to join in prayer with them, let them be deposed and deprived of communion [excommunicated]. If any bishop or priest or deacon shall join in prayer with heretics, let him be suspended from communion.”

Council of Carthage: “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 Laodicea, Canon 33 (A.D. 364): “No one shall join in prayers with heretics or schismatics.”

Apostolic Constitutions, Canon 65: “If any one, either of the clergy or laity, enters into a synagogue of the Jews or heretics to pray, let him be deprived and suspended.”

1917 Code of Canon Law, Canon 823: “Mass may not be said in churches of heretics or schismatics, even though they were in the past properly consecrated or blessed.”

Pope Innocent III, Fourth Lateran Council, 1215: “Moreover, we determine to subject to excommunication believers who receive, defend, or support heretics.”

1917 Code of Canon Law, Canon 1258.1: “It is unlawful for the faithful to assist in any active manner, or to take part in the sacred services of non-Catholics.”

In 1636 the Sacred Congregation for the Propagation of the Faith decreed that Catholics are not only banned from singing an acclamation for the schismatic Patriarchs of Constantinople but added that since the Patriarchs were also heretics they deserved to be cursed instead. (Rev. Szal, Communication of Catholics with Schismatics, CUA Canon Law Studies 264, Washington, CUA 1948, p. 182.)

St Robert Bellarmine, De Romano Pontifice, lib. IV, c. 9, no. 15.: “For men are not bound, or able to read hearts; BUT WHEN THEY SEE THAT SOMEONE IS A HERETIC BY HIS EXTERNAL WORKS, THEY JUDGE HIM TO BE A HERETIC PURE AND SIMPLE, AND CONDEMN HIM AS A HERETIC.”

1917 Code of Canon Law, Canon 1325§1: “Obligation to Profess the Faith. The faithful are bound to profess their faith openly whenever under the circumstances silence, evasion, or their manner of acting would otherwise implicitly amount to a denial of the faith, or would involve contempt of religion, an offense to God, or scandal to the neighbor.”

Pope Pius IX, Sept. 16, 1864, letter to the English Episcopate (CH 254): “That Christians and ecclesiastics should pray... under the direction of heretics and, what is worse, according to an intention which is radically impregnated and vitiated with heresy [such as a heretical mass presided over by a heretical priest that prays in communion with the apostate Vatican II sect and its antipope], is absolutely impossible to tolerate!”

Holy Office Decree, June 22, 1859: “Communication with heretics can be either in a condemned doctrine, or in rites and other signs indicative of adherence to a false [non-Catholic] sect, with the accompanying scandal of the faithful, to whom the Church therefore forbids this communion, lest the faith be lost or endangered. Whence St. John the Evangelist strictly commands: ‘if anyone comes to you and does not bring this (i.e., the Catholic) doctrine, do not receive him into the house, or say to him, Welcome. For he who says to him, Welcome, is sharer in his evil works.’ II John 20. These words evidently imply that everything is forbidden that is expressed by a welcome, in so far as it constitutes liturgical actions instituted to signify ecclesiastical unity. Wherefore we read that a law was enacted by the Fathers of the Council of Carthage ‘against praying or singing with heretics’ as is cited by Benedict XIV. It is therefore illicit to invite heretics to a choir during sacred services, to sing alternately with them, to give them peace or sacred ashes and other such tokens of external worship [with or in front of them], which are rightly and reasonably regarded as signs of interior bond and agreement. This is to be done neither in the active sense, namely by giving them such things, or in the passive sense, by accepting from them in their sacred services.” (SO Instruction Communicatio, 22 June 1859, in Collectanea S. Cong. de Prop. Fide 1:1176)