The Catholic Church is the Mystical Body of Christ.  The Body is easily recognizable and has overwhelming motives of credibility,  and it has for its Soul the Holy Spirit. Pope John Paul I said, “It is clear that Jesus and the Christians, Jesus and the Church are the same thing: indissoluble, inseparable.”  Elements of the Church found outside of the Church “tend and conduct toward the Catholic Church”. 
“[T]he Church of Christ is present and operative” in the Orthodox churches,  in terms of the sacraments and individuals. The Orthodox retain and act as “means of salvation”,  but sacraments are only efficacious for those of good will; the Orthodox maintain the Eucharist, but those willfully separated from the Church “do not receive the fruit of the sacrifice”.  Sacraments in Orthodox churches are efficacious for Catholics in need. 
“Eastern Christians who are in fact separated in good faith” are allowed to receive the Eucharist from Catholic priests, “if they ask of their own accord and have the right dispositions”;  they have no schismatic mindset.  “Someone baptized and brought up in an alien sect will inevitably be, for a time anyway, merely in material heresy or schism. … At what point one brought up in such a sect formally adheres to heresy or schism is God’s business…” 
Especially since many among the Orthodox have been under-catechized or lived in remote areas — their leaders would often just allow Latin missionaries to catechize their flocks  — ignorance of their leaders’ heresy and schism has been at least temporarily possible, like with Catholics who unintentionally followed antipopes (thus not falling into formal schism ). They may also have no other priests regularly available. Thus, they do not lose charity in accepting sacraments from them, and they are only putatively “Orthodox”; they do not have the mindset of schismatics, though they are in a disordered situation. Charles Coulombe wrote in Desire & Deception, “As long as one believes the traditional faith, has been baptized, and accepts the supremacy of the Pope, he is a Catholic, whatever his circumstances — indeed, whatever the dispositions (heretical, schismatic, or orthodox) of the clerics around him.”
And they can have faith without obstinate denial of dogmas, actively trying to learn.  They can find the Faith in their creeds, liturgies, and saints’ writings.  Their leaders’ “negations of Catholic teaching are not on the level of dogma”,  and all that we believe (like the Immaculate Conception ) may be found among them. Papal primacy is also acceptable to them.  There have been occasions when explicit knowledge of the Holy See does not appear to have been given (e.g., for those baptized by St. Peter Claver ); so, there can be such a thing as implicit submission to the Pope, at least temporarily, for those who have not maliciously refused to acknowledge him as head of the Church.  An obstinate rejection of the Papacy is a rejection of all those under the pontiff and nothing short of a rejection of Christ’s Church. “By its very nature, faith is open to the ‘We’ of the Church; it always takes place within her communion.” 
It is possible for one to be faithful, trusting “that the learned believe aright” and having at least an implicit faith in everything proposed by the Magisterium, yet be unaware of or misinformed about some teaching.  However, we cannot take what we like from the Church and reject the rest, bending authority to our own whims; “partial communion” in this way saves no one. Adherence to error is not salvific. A person is saved despite any innocent association with a false sect and because of his relationship with Christ’s Mystical Body. “If one chooses to disbelieve a single article of faith, then the gift of infused faith is no longer available and he can then no longer give full assent to any of the teachings of the Church.” 
St. Augustine said that “neither do the heretics belong to the Church catholic, which loves God; nor do the schismatics form a part of the same”. (Schismatics are those who “in wicked separations break off from brotherly charity, although they may believe just what we believe”.)  But he also said that those “without obstinate ill will, especially those who have not originated their own error by bold presumption, but have received it from parents who had been led astray and had lapsed, those who seek truth with careful industry, ready to be corrected when they have found it” are in a different situation.  Those who have caused divisions are bad. “But,” Cardinal Charles Journet writes, “their followers in later times, who inherit a patrimony of schism or heresy from their birth, are not culpable on that account. They can grow in spiritual stature by remaining in good faith. The sanctifying influence of the sacraments, no longer finding the same obstacles in the will, can result in graces of a high order.”  Those who have not chosen against the Church are more under heretics or schismatics than they are heretics or schismatics. It is, however, better to presume that there is at least culpable negligence among them (for which they would be punished ), so that they might be saved and so that we do not neglect our duty to evangelize.
Br. André Marie, M.I.C.M., says, “There are many people who would not be considered ‘formal’ members of the Church who are, in fact, Catholics in the dogmatic sense. … What is important are not the ‘juridical’ issues, but the ecclesiological, sacramental, and ‘creedal’ elements that truly make one a Catholic. Perhaps we can put it in terms that might make a canonist cringe: de facto Catholicism is what matters, not de jure Catholicism.”  Fr. John J. King, O.M.I., would say, “They are vivified by the Holy Spirit because of the tenuous but true union they have with the Body of Christ. This is not an attempt to give a new meaning to the old word ‘extra.’ It is simply a conclusion forced upon them by the full realization, according to the analogia fidei, of what the Church’s understanding of this dogmatic word has always been.” 
Here, I should address “invincible ignorance”, often an exaggerated thing. It is that which “cannot be overcome by study”.  An absolute invincible ignorance (meaning, the impossibility of learning even “truths necessary for salvation“) would not save.  (Moreover, a Catholic cannot know if someone is “invincibly ignorant” of the Faith. And how is it possible for the Catholic to know it, but impossible for those with whom he comes into contact?) Salvation comes from sanctifying grace. We need supernatural divine faith, hope, and charity. Some say that the faithless might die that way “through no fault of their own”, but St. Thomas Aquinas could say that even the proverbial man on an island could be saved, “[f]or it pertains to divine providence to furnish everyone with what is necessary for salvation, provided that on his part there is no hindrance”.  Ignorance is a lack of something, and lacking something gains us nothing. A relationship can never be based on a lack of something, but must involve reciprocity. Whatever the reason for a lack of reciprocity to God in response to His grace, it cannot ever be justified. 
“God Himself has made known to mankind the way in which men are to serve Him” and “all men are bound to seek the truth, especially in what concerns God and His Church”.  All must “enquire whether or not God has Himself revealed definitively and infallibly how He wishes to be known, loved, and served”,  and, in matters spiritual, where there’s a will, there’s a way; “seek, and you shall find” (Matthew 7:7). “[T]hat faith without which it is impossible to please [God]” can be transmitted in ordinary and extraordinary ways, as evidenced throughout history.  “[A]ll are capable of receiving the doctrines of the faith.”  If Catholics budge on the necessity of faith, then we give ammunition to the Protestant apologists who have accused us of promoting “works-based salvation”. It is wrong to think that “we need only seek that Christians should be good Christians, Muslims good Muslims, Hindus good Hindus, and so forth”. 
We are all given sufficient chance to be saved, either rejecting or accepting it, though Orthodox naturally have more available to them than Protestants, who so often define themselves against Catholicism, justify sins and disbelieve the need for good works (thus rejecting God as Rewarder), lack priesthood, increasingly doubt the crucial dogmas of the Trinity and the Incarnation, and sometimes do not even have baptism. There are also those who favor a view that matter is eternal (like Mormons) and deny God as Creator of everything.  Those who treat nothing as absolutely true and binding, leaving everything up to individual interpretation, show human and not divine faith. Bl. John Henry Newman said, “Protestants, generally speaking, have not faith, in the primitive meaning of that word”.  Faith is often replaced with emotional consolations. One who rejects oneness, holiness, catholicity, and apostolicity cannot say the Creeds sincerely. Orthodox can be thankful that they are not exposed to as many temptations to err.
Politics and personal suffering cannot be excuses to reject the Church’s teachings (even for, say, those who suffered under Crusaders); those who try to use these are, like St. Augustine admitted of his past self, readier to impose falsehood than to be informed of the truth.  When people hear of the Pope as “Antichrist” or the Church as “Whore of Babylon”, they are no doubt at first incredulous, and so they are obliged to investigate.
Doubt can come to an Anglican sitting in a church he knows to be stolen, a Lutheran hearing of “Reformation Day”, a Methodist discovering that his views do not line up with those of a saint, a Baptist wondering how books’ infallibility can be known, and so on. They can also doubt when they come into contact with each other. But if they refuse to hear (Scripture contrasts hearing and reading ), do not follow promptings by the Spirit, and are malicious, they can be lost forever. If one cooperates with God, he will receive more and more graces. However, if he resists or abuses them, he is not guaranteed more. (Some imagine that no one would really defy what he knows to be true, but we ourselves disprove this every single time we commit mortal sin.)
Catholics should be concerned for them. Unless their contrition is perfect (with the firm resolution to sin no more and with love for God above all else and as the prevailing motive, not fear of Hell or any other reason), even nominal “Protestants” will die in their mortal sins, since “imperfect contrition cannot obtain the forgiveness of grave sins, but it disposes one to obtain forgiveness in the sacrament of Penance”.  They will be condemned for sins that, without the sacraments, will be difficult to avoid. The Orthodox, however, have the sacraments. 
All must “return” to the Church, individually or corporately. Yet, as Pope Benedict XVI, the father of the Anglican Ordinariates,  noted in 2005, this “does not mean uniformity in all expressions of theology and spirituality, in liturgical forms and in discipline”.  Again, the Orthodox are in a special position. A 1992 CDF document says that they “merit the title of particular Churches”, but “their existence as particular Churches is wounded”.  The Orthodox have long been conceded the title of “Churches”,  but “to be fully Church…there must be…the supreme authority of the Church”.  A particular Church “can be truly complete only through effective communion in faith, sacraments and unity with the whole Body of Christ”.  “The Eucharist objectively creates a powerful bond of unity between the Catholic Church and the Orthodox Churches,”  but “it is an intrinsic requirement of the Eucharist that it should be celebrated in communion” with the Church’s hierarchical order.  It is clear that acceptance of the Papacy is a non-negotiable.
Of Orthodox in particular, “we can say that in some real way they are joined with us in the Holy Spirit, for to them too He gives His gifts and graces whereby He is operative among them with His sanctifying power”. However, one cannot separate himself from the Church on earth without also separating himself from the Church in Heaven, and graces always have the true Church as their end. The good among them “desire to be peacefully united, in the manner determined by Christ, as one flock under one shepherd”.  Many Orthodox today are “in good faith” and “are desirous of reunion with the Apostolic See of Rome”. 
History is complicated: there have been instances of communicatio in sacris, times when lines were blurred, and periods of reunion. Conversion and regularization were always the ends (e.g., the Pope would be remembered in concelebrations).  We can look to Bl. Pope Pius IX, who, with Arcano Divinae Providentiae, even invited the Orthodox to participate in the First Vatican Council.  Now, with the mutual excommunications (which were “censures against the persons concerned and not the Churches” ) lifted, may we be together again.
John 17:11 (DRA): “And now I am not in the world, and these are in the world, and I come to thee. Holy Father, keep them in thy name whom thou has given me; that they may be one, as we also are.”
1. See Thomas Storck, “What is the Church of Jesus Christ?” (Homiletic & Pastoral Review, vol. 108, no. 6, March 2008, p. 24-31, 42-45; available through the author’s website: http://www.thomasstorck.org/theological-topics).
2. See Dr. Lawrence Feingold’s “Motives of Credibility for Faith” (http://web.archive.org/web/20140104144437/http://www.hebrewcatholic.net/wp-content/uploads/2013/11/12.07-motives-of-credibility-for-faith-pdf.pdf) and James Likoudis’ “The Marks Of The Church And Eastern Orthodoxy” (http://www.catholicculture.org/culture/library/view.cfm?recnum=4752).
3. General Audience, 13 September 1978 (http://w2.vatican.va/content/john-paul-i/en/audiences/documents/hf_jp-i_aud_13091978.html)
4. CDF, Notification on Leonardo Boff (http://www.vatican.va/roman_curia/congregations/cfaith/documents/rc_con_cfaith_doc_19850311_notif-boff_en.html)
6. Second Vatican Council, Unitatis Redintegratio §3 (http://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_decree_19641121_unitatis-redintegratio_en.html)
7. Summa Theologiae, TP, Q. 82, Art. 7, Ans. (http://newadvent.org/summa/4082.htm)
8. Canon 844 §2 (http://www.vatican.va/archive/ENG1104/__P2T.HTM). Archimandrite Ambrosius (Pogodin): “In one of its decrees the Vatican Council felt it possible and even desirable that Roman Catholics finding themselves beyond the vicinity of a Catholic Church, could receive the holy sacraments, including Holy Communion, from Orthodox Churches in their vicinity. Only the Moscow Patriarchate responded to this and announced a decision favorable to the Catholics, allowing them to receive Communion in Orthodox Churches where there were no Roman Catholic churches. This decision was accepted by the Patriarchal Synod on December 16, 1969 and was also affirmed at a later date.” (“On the Question of the Order of Reception of Persons into the Orthodox Church”, Appendices; http://www.holy-trinity.org/ecclesiology/pogodin-reception/reception-appendices.html)
9. Second Vatican Council, Orientalium Ecclesiarum §27 (http://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_decree_19641121_orientalium-ecclesiarum_en.html)
10. In the 43rd episode of his online show, Charles Coulombe mentions that Fr. Feodor Wilcock, S.J. (a priest of the Russian rite and a friend of Fr. Leonard Feeney, S.J.), “would never refuse an Orthodox communion, because he knew that any Orthodox that would come to a Catholic priest to receive was already in the right frame of mind”.
11. See Brother André Marie’s “Promising Salvation to Non-Catholics: A Sin against Charity” (http://catholicism.org/ad-rem-no-145.html) and comments on Coptic Orthodox (http://catholicism.org/the-twenty-one-slain-copts-martyrs.html). Material heretics and schismatics are not considered legal members of the Church, but they can be saved by a desire for membership (Fr. Ludwig Ott, Fundamentals of Catholic Dogma, ISBN 978-1-929291-85-4, p. 311).
12. A. Edward Siecienski, The Papacy and the Orthodox: Sources and History of a Debate (ISBN 9780190245269), p. 348, footnotes. Catholic Encyclopedia, “Greek Church” (http://www.newadvent.org/cathen/06752a.htm): “…in the seventeenth and eighteenth centuries the Jesuits and Capuchins were allowed to preach and hear confessions in the Greek Churches, by the express permission of the patriarch and the bishops.”
13. Catholic Encyclopedia, “Schism” (http://www.newadvent.org/cathen/13529a.htm). “In the material sense of the word there is schism, that is rupture of the social body, if there exist two or more claimants of the papacy, each of whom has on his side certain appearances of right and consequently more or less numerous partisans. But under these circumstances good faith may, at least for a time, prevent a formal schism; this begins when the legitimacy of one of the pontiffs becomes so evident as to render adhesion to a rival inexcusable.” St. Vincent Ferrer, though he accepted an antipope and was thus objectively wrong in identifying the visible Church, acted in good faith (http://www.ewtn.com/saintsHoly/saints/V/stvincentferrer.asp).
14. See Charles Coulombe’s “Looking Eastward” (http://www.catholicculture.org/culture/library/view.cfm?recnum=6082).
15. See, for example, Dave Armstrong’s The Quotable Eastern Church Fathers (Lulu, 2013; ISBN 978-1-304-21000-5).
16. Antonio Parisi, “Orthodoxy Is My Doxy” (http://jameslikoudispage.com/Ecumenic/orthetero.htm)
17. James Likoudis, “The Immaculate Conception and the Doctrine of Mary as Coredemptrix in Eastern Orthodoxy” (http://jameslikoudispage.com/Ecumenic/marycorede.htm). See also: “Catholics of Egypt Gratified by Schismatic Copts’ Defense of Assumption Dogma in Controversy”, 20 November 1950 (http://thecatholicnewsarchive.org/cgi-bin/crra?a=d&d=cns19501120-01.1.28).
18. See James Likoudis, “Testimony to the Primacy of the Pope by a 17th c. Russian Orthodox Prelate” (http://jameslikoudispage.com/Ecumenic/pmohila.htm) and “Light from the ‘Church of the East’ on the Roman Primacy” (http://jameslikoudispage.com/Ecumenic/assyrians.htm).
19. See Br. Michael’s “Slave of the Slaves: the Story of Saint Peter Claver” (http://catholicism.org/slave-of-slaves.html). “The holy man had no time to lose” before those coming in from slave ships “would be auctioned off in the market place and sometimes end up far away”. He was known to preach simply.
20. Canon 751: “schism is the refusal of submission to the Supreme Pontiff or of communion with the members of the Church subject to him” (http://www.vatican.va/archive/ENG1104/__P2H.HTM). Also, one becomes subject to the Church, and therefore to the Pontiff, at baptism. Explicit knowledge of the Papacy has never been considered essential in emergency instruction. Msgr. Joseph C. Fenton notes that “it is the common teaching of the theologians that true supernatural faith can exist even where there is only an implicit belief in the Catholic Church” (The Catholic Church and Salvation, The Newman Press, 1958, p. 69). Though there has been invincible ignorance of the Holy See, when writing of the Papacy and the Church’s Roman-ness, Cardinal Charles Journet saw fit to mention, “When the Christian communities of the Far East, converted from paganism by St. Francis Xavier, and left without priests for two hundred years, once more saw new missionaries disembark, they recognized them simply by asking whether they obeyed the ‘white robe’.” (http://www.ewtn.com/library/THEOLOGY/chwordin3.htm) And, in the early Church, “Even the pagans knew that a true Christian was one in communion with the bishop of Rome,” according to Fr. Ludwig Hertling, S.J. (http://cathedraunitatis.wordpress.com/2007/09/04/ludwig-hertling-on-communio-and-the-roman-church-1/).
21. Pope Francis, Lumen Fidei §39 (http://w2.vatican.va/content/francesco/en/encyclicals/documents/papa-francesco_20130629_enciclica-lumen-fidei.html)
22. Summa Theologiae, SSP, Q. 2, Art. 6, R. to Ob. 3 (http://www.newadvent.org/summa/3002.htm)
23. Steven J. Rummelsburg, “Give Full Assent to the Teachings of the Church” (http://www.integratedcatholiclife.org/2016/10/rummelsburg-give-full-assent-to-the-teachings-of-the-church/)
24. De Fide Et Symbolo, chapter 10 (http://www.clerus.org/bibliaclerusonline/en/ce5.htm)
25. The Fathers of the Church: Saint Augustine Letters, Volume I (1-82) (translated by Sister Wilfrid Parsons, S.N.D.; ISBN 978-0-8132-1556-3), p. 182
26. The Church of the Word Incarnate (http://www.ewtn.com/library/THEOLOGY/chwordin3.htm). Msgr. Fenton says that “some of the members of these dissident and schismatical communities may receive the Eucharist and take part in the Eucharistic sacrifice fruitfully” (The Catholic Church and Salvation, p. 94), and “any man who fruitfully and worthily partakes of this Eucharistic feast is within the true Church, at least by intention” (p. 24). “Neither justification nor glorification — that is, neither the remission of our sins nor the attainment of the Beatific Vision — is possible except ‘in Christ Jesus.’ And the Church, in the divinely inspired epistles of St. Paul, is represented precisely though metaphorically as ‘the body of Christ.’ To be ‘in Christ Jesus,’ then, is to be ‘within’ the Mystical Body of Christ, Our Lord’s one and only true Church or kingdom.” (p. 22-23) “All of those outside the Church, even the individuals who have committed no sin against the faith itself, are in a position in which they cannot be saved unless they in some way enter or join the Church before they die.” (p. 40) “…if [a man] has the love of charity for God, he is ‘within’ the true Church of Jesus Christ, at least by sincere (although perhaps merely implicit) intention and desire. If, on the other hand, a man has not a love of charity for God, he is in the state of sin.” (p. 46) Those with faith, hope, and charity have “the spiritual or inner bond of unity within the Catholic Church” and are “by that very fact joined to Our Lord and to His disciples within the supernatural kingdom of God” (p. 62).
27. Fr. Bernard J. Otten, S.J., writes in The Business of Salvation (B. Herder, 1916), “…if anyone through his own fault, whether through obstinacy or through culpable negligence, fails to become a member of the Church which Christ has established on earth, he is by that very fact deprived of the means necessary for saving his soul” (p. 250-251). While desire to be in the Church, included in the firm will to do all that God requires, is an absolute necessity, because there are real cases in which attaining legal membership is impossible, we know that “membership” is a relative necessity, meaning that those who can die as members must (see John Salza and Robert Siscoe, True or False Pope?, ISBN 978-1-4951-8142-9, p. 132-137).
28. “Promising Salvation to Non-Catholics”. Pope Pius XI wrote in Ecclesiam Dei §9 that St. Josaphat Kuntsevych, though “born of schismatic parents”, “always considered himself a member” of the true Church (http://www.papalencyclicals.net/pius11/p11eccle.htm). For example, Francis E. Hyland wrote that the question of legal membership for excommunicates “seems to be one of theory and of little practical import”, since they lack benefits of membership and could still be saved by perfect contrition (Excommunication, Catholic University of America, 1928, p. 5-10). A person who passed away with sanctifying grace must have been sufficiently in accord with the Church, having all essentials and being without mortal sin, even if this accord was not recognized. According to Fenton, “…charity is absolutely incompatible with an unwillingness to live and die in the communion of the Church of Jesus Christ. … Thus every man who has charity, every man in the state of grace, every man who is saved, is necessarily one who is or who intends to become a member of the Roman Catholic Church. There can be no exceptions.” (This intent can be implicit for those not “fully informed about the identity of the true Church”.) Fenton says “[t]his is the only interpretation fully consonant with” the declarations of the Fourth Lateran Council, the Council of Florence, and Pope Boniface VIII (“Extra Ecclesiam Nulla Salus”, The American Ecclesiastical Review, unknown issue, p. 303-304; http://thecatholicarchive.com/wp-content/uploads/2013/01/106.pdf). The existence of just individuals who are not “members” no more contradicts the coextension of the Catholic Church and the Mystical Body of Christ than does the existence of sinful members.
29. The Necessity of the Church for Salvation in Selected Theological Writings of the Past Century (Catholic University of America, 1960), p. 357
30. Summa Theologiae, PSP, Q. 76, Art. 2, Ans. (http://newadvent.org/summa/2076.htm)
31. See §2 of Pope St. Pius X’s Acerbo Nimis (http://www.papalencyclicals.net/Pius10/p10chdoc.htm). A misinterpretation of words of Bl. Pope Pius IX can lead some to think that there are non-Christians perfectly obeying the natural law and remaining without mortal sin and being saved that way. Msgr. Fenton wrote that “no one can remain for any considerable time without committing mortal sin apart from the aid of supernatural grace” and without having sanctifying grace, and so “the man who is sedulously observing the natural law in such a way as to avoid mortal sin for a considerable period of time is one who has already made an explicit act of supernatural faith, in which the belief in the Church was at least implicitly contained” (“The Theological Proof for the Necessity of the Catholic Church: Part II”, The American Ecclesiastical Review, unknown issue, p. 299; http://thecatholicarchive.com/wp-content/uploads/2013/01/40.pdf).
32. Questiones Disputatae de Veritate, Q. 14, A. 11, A. to D. 1 (http://dhspriory.org/thomas/QDdeVer14.htm). Those with the good will to comply with God’s will are given the Truth, which they accept when it is sufficiently proposed to them. See Br. Thomas Mary Sennott’s “The Salvation of the Pre-Columbian Amerindians” (http://catholicism.org/eens-salvation-amerindian.html) and Mary Rezac’s “Did this Spanish nun bi-locate to Texas?” (http://www.catholicnewsagency.com/news/did-this-spanish-nun-bi-locate-to-texas-vatican-aims-to-find-out-60292/). For more on opportunity for salvation, see Msgr. Joseph Pohle and Arthur Preuss, Grace: Actual and Habitual (2nd Revised Ed., 1917), p. 152-187.
33. “…endowed as they are with free will, they can misuse their freedom under the impulse of mental agitation and base desires. Unfortunately many are still wandering far from the Catholic truth, being unwilling to follow the inspirations of divine grace, because neither they nor the faithful pray to God with sufficient fervor for this intention.” (Mystici Corporis Christi §104; http://w2.vatican.va/content/pius-xii/en/encyclicals/documents/hf_p-xii_enc_29061943_mystici-corporis-christi.html)
34. Second Vatican Council, Dignitatis Humanae §1 (http://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_decl_19651207_dignitatis-humanae_en.html)
35. Bl. Pope Paul VI, Ecclesiam Suam §107 (http://w2.vatican.va/content/paul-vi/en/encyclicals/documents/hf_p-vi_enc_06081964_ecclesiam.html)
36. Catechism of the Catholic Church §848 (http://www.scborromeo.org/ccc/p123a9p3.htm#848)
37. Pope Paul III, Sublimus Dei (http://www.newadvent.org/library/docs_pa03sd.htm)
38. Cardinal Joseph Ratzinger, 1988 (http://www.catholicculture.org/culture/library/view.cfm?recnum=3032)
39. “There can be real divine faith when a man believes explicitly, on the authority of God revealing, the existence of God as the Head of the supernatural order, the fact that God rewards good and punishes evil, and the doctrines of the Blessed Trinity and of the Incarnation.” (The Catholic Church and Salvation, p. 69) Fr. Brian Harrison, O.S., citing Scripture, magisterial statements, and liturgy, has powerfully argued in a speech entitled “Can an Implicit Faith in Christ Be Sufficient for Salvation?” for the absolute necessity of explicit belief in all of these (http://store.catholicism.org/can-an-implicit-faith-in-christ-be-sufficient-for-salvation-mp3.html).
40. Discourse 10: “Faith and Private Judgment” (http://www.newmanreader.org/works/discourses/discourse10.html). For early Christians, “The Church was their teacher; they did not come to argue, to examine, to pick and choose, but to accept whatever was put before them. No one doubts, no one can doubt this, of those primitive times. A Christian was bound to take without doubting all that the Apostles declared to be revealed”. For many now, “what looks like faith, is a mere hereditary persuasion, not a personal principle”. Putative Protestants “who firmly believe in spite of all difficulties, they certainly have some claim to be considered under the influence of faith; but there is nothing to show that such persons, where they are found, are not in the way to become Catholics, and perhaps they are already called so by their friends, showing in their own examples the logical, indisputable connexion which exists between possessing faith and joining the Church”.
41. “…I should either even then have defended the Catholic Scriptures attacked by the Manichæans, if as I say, I had been cautious; or I should now show that they can be defended.” (Of Two Souls, Chapter 15; http://www.newadvent.org/fathers/1403.htm) Once finding himself unable to answer a question, St. Augustine felt “admonished from on high to leave that error and to be converted to the Catholic faith or rather to recall it, by the indulgence of Him who did not permit [him] to inhere forever in this fallacy” (Disputation Against Fortunatus, Second Day; http://www.newadvent.org/fathers/1404.htm). Pope Pius XI said that those who “humbly beg light from heaven” “will recognize the one true Church of Jesus Christ and will, at last, enter it, being united with us in perfect charity” (Mortalium Animos §13; http://w2.vatican.va/content/pius-xi/en/encyclicals/documents/hf_p-xi_enc_19280106_mortalium-animos.html).
42. Orlando Fedeli, “Read the Bible?” (http://www.catholicapologetics.info/apologetics/protestantism/read.htm)
43. Catechism of the Catholic Church §1451-1453 (http://www.scborromeo.org/ccc/p2s2c2a4.htm#1451)
44. According to Cardinal Journet, “…the dissident Churches which retain the power of order (the dissident Oriental Churches for instance), may retain, by a concession of the Sovereign Pontiff, either express or tacit, a partial but genuine jurisdiction which enables them validly to administer to their subjects even those sacraments which require a jurisdictional power in the minister; such as Confirmation and Penance. ….the validity of the Confirmation given by the dissident priests, a validity that could only result from a concession of the Sovereign Pontiff, was explicitly recognized by the Holy Office (3rd July 1859) for all the Oriental Churches, save those of Bulgaria, Cyprus, South Italy and the islands adjacent from whom this concession had been earlier withdrawn. … As to the sacrament of Penance, we know that ‘in peril of death all priests, even those not approved for hearing confessions, can validly and licitly absolve any penitents from all sins and censures.’ There then is a definite case in which the dissident Oriental priests certainly receive from the Sovereign Pontiff every authorization to dispense the sacrament of Penance. ….(1) The Church, which has not withdrawn from them the jurisdiction needed for Confirmation, will not deprive them of the still more useful jurisdiction to absolve their flock from their sins; (2) Rome has never required Eastern converts to make a general confession; and must thus regard confessions made in good faith to dissident priests as valid.” (http://www.ewtn.com/library/THEOLOGY/chwordin3.htm)
45. See Anglicanorum Coetibus (http://w2.vatican.va/content/benedict-xvi/en/apost_constitutions/documents/hf_ben-xvi_apc_20091104_anglicanorum-coetibus.html).
46. Address at Ecumenical Meeting in Cologne, 19 August 2005 (http://w2.vatican.va/content/benedict-xvi/en/speeches/2005/august/documents/hf_ben-xvi_spe_20050819_ecumenical-meeting.html). Fr. Yves Congar, O.P., said that “union, while not representing an ‘absorption’ in the odious sense of the word, can only be, from the point of view of ecclesiology, a reunion with the Apostolic See” (After Nine Hundred Years, Fordham University Press, 1959, p. 82).
47. CDF, “On Some Aspects of the Church Understood as Communion” §17 (http://www.vatican.va/roman_curia/congregations/cfaith/documents/rc_con_cfaith_doc_28051992_communionis-notio_en.html)
48. Preparatory Schema for Lumen Gentium, chapter XI, notes (translated by Fr. Joseph A. Komonchak; http://jakomonchak.files.wordpress.com/2013/07/draft-of-de-ecclesia-chs-1-11.pdf)
49. “On Some Aspects” §13
50. Pope St. John Paul II, Address to U.S. Bishops, 16 September 1987 (http://w2.vatican.va/content/john-paul-ii/en/speeches/1987/september/documents/hf_jp-ii_spe_19870916_vescovi-stati-uniti.html)
51. Pope Benedict XVI, Sacramentum Caritatis §15 (http://w2.vatican.va/content/benedict-xvi/en/apost_exhortations/documents/hf_ben-xvi_exh_20070222_sacramentum-caritatis.html)
52. Pope St. John Paul II, Ecclesia de Eucharistia §35 (http://www.vatican.va/holy_father/special_features/encyclicals/documents/hf_jp-ii_enc_20030417_ecclesia_eucharistia_en.html)
53. Second Vatican Council, Lumen Gentium §15 (http://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_const_19641121_lumen-gentium_en.html)
54. James Likoudis, “History of the Byzantine Greco-Slav Schism” (http://jameslikoudispage.com/Ecumenic/byschism.htm)
55. See James Likoudis’ “A Formal Schism in 1054 A.D.?” (http://jameslikoudispage.com/Ecumenic/pamiccer.htm), William Huysman’s “Why God Led Me to Rome Instead of Constantinople” (http://web.archive.org/web/20180213114036/http://thebananarepublican.blogspot.com/2011/04/old-rome-not-new-rome-1.html), the first chapter of Fr. Serge Descy’s The Melkite Church (Sophia Press, 1993), a series from the Transalpine Redemptorists (http://papastronsay.blogspot.com/search/label/Communicatio%20in%20sacris), and Fr. John Hunwicke on ecumenism (http://liturgicalnotes.blogspot.com/2016/02/ecumenism-update.html).
56. They were “not only invited but exhorted and begged”. “…if these men had gone to the Vatican Council as their predecessors had gone to Second Lyons and to Florence, they could have become members of this council with the right of deliberative vote.” (Fenton, “The Ecumenical Council and Christian Reunion”, The American Ecclesiastical Review, Vol. CXLI, July-December 1959, p. 45-57)
57. Joint Catholic-Orthodox Declaration, 7 December 1965 (http://w2.vatican.va/content/paul-vi/en/speeches/1965/documents/hf_p-vi_spe_19651207_common-declaration.html)